netdisco / snmp-info

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NAME SNMP::Info - OO Interface to Network devices and MIBs through SNMP

VERSION SNMP::Info - Version 3.972002

AUTHOR SNMP::Info is maintained by team of Open Source authors headed by Eric Miller, Bill Fenner, Max Baker, Jeroen van Ingen and Oliver Gorwits.

Please visit <https://github.com/netdisco/snmp-info/> for the most
up-to-date list of developers.

SNMP::Info was originally created at UCSC for the Netdisco project
<http://netdisco.org> by Max Baker.

DEVICES SUPPORTED There are now generic classes for most types of device and so the authors recommend loading SNMP::Info with AutoSpecify, and then reporting to the mail list any missing functionality (such as neighbor discovery tables).

SYNOPSIS use SNMP::Info;

 my $info = SNMP::Info->new({
                            # Auto Discover your Device Class (Cisco, Juniper, etc ...)
                            AutoSpecify => 1,
                            Debug       => 1,

                            # The rest is passed to SNMP::Session
                            DestHost    => 'router',
                            Community   => 'public',
                            Version     => 2

                            # Parameter reference for SNMPv3
                            # Version   => 3
                            # SecLevel  => 'authPriv', # authPriv|authNoPriv|noAuthNoPriv
                            # SecName   => 'myuser',
                            # AuthProto => 'MD5',      # MD5|SHA
                            # AuthPass  => 'authp4ss',
                            # PrivProto => 'DES',      # DES|AES
                            # PrivPass  => 'pr1vp4ss',
                           });

 my $err = $info->error();
 die $err if defined $err;
 # usually a wrong DestHost or Community or Version if you have trouble here

 my $name  = $info->name();
 my $class = $info->class();
 print "SNMP::Info is using this device class : $class\n";

 # Find out the Duplex status for the ports
 my $interfaces = $info->interfaces();
 my $i_duplex   = $info->i_duplex();

 # Get CDP Neighbor info
 my $c_if       = $info->c_if();
 my $c_ip       = $info->c_ip();
 my $c_port     = $info->c_port();

 # Print out data per port
 foreach my $iid (keys %$interfaces){
    my $duplex = $i_duplex->{$iid};
    # Print out physical port name, not snmp iid
    my $port  = $interfaces->{$iid};

    print "$port: ";
    print "$duplex duplex" if defined $duplex;

    # The CDP Table has table entries different than the interface tables.
    # So we use c_if to get the map from cdp table to interface table.

    my %c_map = reverse %$c_if;
    my $c_key = $c_map{$iid};
    unless (defined $c_key) {
         print "\n\n";
         next;
     }
    my $neighbor_ip   = $c_ip->{$c_key};
    my $neighbor_port = $c_port->{$c_key};

    print " connected to $neighbor_ip / $neighbor_port\n" if defined $neighbor_ip;
    print "\n";

 }

SUPPORT Please direct all support, help, and bug requests to the snmp-info-users Mailing List at http://lists.sourceforge.net/lists/listinfo/snmp-info-users.

DESCRIPTION SNMP::Info gives an object oriented interface to information obtained through SNMP.

This module is geared towards network devices. Subclasses exist for a
number of network devices and common MIBs.

The idea behind this module is to give a common interface to data from
network devices, leaving the device-specific hacks behind the scenes in
subclasses.

In the SYNOPSIS example we fetch the name of all the ports on the device
and the duplex setting for that port with two methods -- interfaces()
and i_duplex().

The information may be coming from any number of MIB files and is very
vendor specific. SNMP::Info provides you a common method for all
supported devices.

Adding support for your own device is easy, and takes little SNMP
knowledge.

The module is not limited to network devices. Any MIB or device can be
given an objected oriented front-end by making a module that consists of
a couple hashes. See EXTENDING SNMP::INFO.

REQUIREMENTS

  1. Net-SNMP To use this module, you must have Net-SNMP installed on your system. More specifically you need the Perl modules that come with it.

    DO NOT INSTALL SNMP:: or Net::SNMP from CPAN!
    
    The SNMP module is matched to an install of net-snmp, and must be
    installed from the net-snmp source tree.
    
    The Perl module "SNMP" is found inside the net-snmp distribution. Go
    to the perl/ directory of the distribution to install it, or run
    "./configure --with-perl-modules" from the top directory of the
    net-snmp distribution.
    
    Net-SNMP can be found at http://net-snmp.sourceforge.net
    
    Version 5.3.2 or greater is recommended.
    
    Versions 5.0.1, 5.0301 and 5.0203 have issues with bulkwalk and are
    not supported.
    
    Redhat Users: Some versions that come with certain versions of
    Redhat/Fedora don't have the Perl library installed. Uninstall the
    RPM and install by hand.
  2. MIBS SNMP::Info operates on textual descriptors found in MIBs.

    If you are using SNMP::Info separate from Netdisco, download the
    Netdisco MIB package at
    <https://github.com/netdisco/netdisco-mibs/releases/latest/>
    
    Make sure that your snmp.conf is updated to point to your MIB
    directory and that the MIBs are world-readable.

DESIGN GOALS

  1. Use of textual MIB leaf identifier and enumerated values

    *   All values are retrieved via MIB Leaf node names
    
        For example SNMP::Info has an entry in its %GLOBALS hash for
        ``sysName'' instead of 1.3.6.1.2.1.1.5.
    
    *   Data returned is in the enumerated value form.
    
        For Example instead of looking up 1.3.6.1.2.1.2.2.1.3 and
        getting back 23
    
        SNMP::Info will ask for "RFC1213-MIB::ifType" and will get back
        "ppp".
  2. SNMP::Info is easily extended to new devices You can create a new subclass for a device by providing four hashes : %GLOBALS, %MIBS, %FUNCS, and %MUNGE.

    Or you can override any existing methods from a parent class by
    making a short subroutine.
    
    See the section EXTENDING SNMP::INFO for more details.
    
    When you make a new subclass for a device, please be sure to send it
    back to the developers (via a github pull request or the mailing
    list) for inclusion in the next version.

SUBCLASSES These are the subclasses that implement MIBs and support devices:

Required MIBs not included in the install instructions above are noted
here.

MIB Subclasses These subclasses implement method to access one or more MIBs. These are not used directly, but rather inherited from device subclasses.

For more info run "perldoc" on any of the following module names.

SNMP::Info::AdslLine
    SNMP Interface to the ADSL-LINE-MIB for ADSL interfaces.

    Requires the ADSL-LINE-MIB, down loadable from Cisco.

    See documentation in SNMP::Info::AdslLine for details.

SNMP::Info::Aggregate
    SNMP Interface to IF-MIB "ifStackTable" Aggregated Links

    See documentation in SNMP::Info::Aggregate for details.

SNMP::Info::Airespace
    AIRESPACE-WIRELESS-MIB and AIRESPACE-SWITCHING-MIB. Inherited by
    devices based on the Airespace wireless platform.

    See documentation in SNMP::Info::Airespace for details.

SNMP::Info::AMAP
    ALCATEL-IND1-INTERSWITCH-PROTOCOL-MIB. Alcatel Mapping Adjacency
    Protocol (AMAP) Support.

    See documentation in SNMP::Info::AMAP for details.

SNMP::Info::Bridge
    BRIDGE-MIB (RFC1286). Q-BRIDGE-MIB. Inherited by devices with Layer2
    support.

    See documentation in SNMP::Info::Bridge for details.

SNMP::Info::CDP
    CISCO-CDP-MIB. Cisco Discovery Protocol (CDP) Support. Inherited by
    Cisco, Enterasys, and HP devices.

    See documentation in SNMP::Info::CDP for details.

SNMP::Info::CiscoAgg
    SNMP Interface to Cisco Aggregated Links

    See documentation in SNMP::Info::CiscoAgg for details.

SNMP::Info::CiscoBGP
    CISCO-BGP4-MIB. Cisco BGPv4 support. Inherited by Cisco devices with
    Layer3 support.

    See documentation in SNMP::Info::CiscoBGP for details.

SNMP::Info::CiscoConfig
    CISCO-CONFIG-COPY-MIB, CISCO-FLASH-MIB, and OLD-CISCO-SYS-MIB. These
    OIDs facilitate the writing of configuration files.

    See documentation in SNMP::Info::CiscoConfig for details.

SNMP::Info::CiscoPortSecurity
    CISCO-PORT-SECURITY-MIB and CISCO-PAE-MIB.

    See documentation in SNMP::Info::CiscoPortSecurity for details.

SNMP::Info::CiscoPower
    CISCO-POWER-ETHERNET-EXT-MIB.

    See documentation in SNMP::Info::CiscoPower for details.

SNMP::Info::CiscoQOS
    CISCO-CLASS-BASED-QOS-MIB. A collection of OIDs providing
    information about a Cisco device's QOS config.

    See documentation in SNMP::Info::CiscoQOS for details.

SNMP::Info::CiscoRTT
    CISCO-RTTMON-MIB. A collection of OIDs providing information about a
    Cisco device's RTT values.

    See documentation in SNMP::Info::CiscoRTT for details.

SNMP::Info::CiscoStack
    CISCO-STACK-MIB.

    See documentation in SNMP::Info::CiscoStack for details.

SNMP::Info::CiscoStats
    OLD-CISCO-CPU-MIB, CISCO-PROCESS-MIB, and CISCO-MEMORY-POOL-MIB.
    Provides common interfaces for memory, cpu, and os statistics for
    Cisco devices.

    See documentation in SNMP::Info::CiscoStats for details.

SNMP::Info::CiscoStpExtensions
    CISCO-STP-EXTENSIONS-MIB

    See documentation in SNMP::Info::CiscoStpExtensions for details.

SNMP::Info::CiscoVTP
    CISCO-VTP-MIB, CISCO-VLAN-MEMBERSHIP-MIB,
    CISCO-VLAN-IFTABLE-RELATIONSHIP-MIB

    See documentation in SNMP::Info::CiscoVTP for details.

SNMP::Info::DocsisCM
    SNMP Interface for DOCSIS Cable Modems

    See documentation in SNMP::Info::DocsisCM for details.

SNMP::Info::DocsisHE
    SNMP Interface for DOCSIS CMTS

    See documentation in SNMP::Info::DocsisHE for details.

SNMP::Info::EDP
    Extreme Discovery Protocol. EXTREME-EDP-MIB

    See documentation in SNMP::Info::EDP for details.

SNMP::Info::Entity
    ENTITY-MIB. Used for device info in Cisco and other vendors.

    See documentation in SNMP::Info::Entity for details.

SNMP::Info::EtherLike
    EtherLike-MIB (RFC1398) - Some Layer3 devices implement this MIB, as
    well as some Aironet Layer 2 devices (non Cisco).

    See documentation in SNMP::Info::EtherLike for details.

SNMP::Info::FDP
    Foundry (Brocade) Discovery Protocol. FOUNDRY-SN-SWITCH-GROUP-MIB

    See documentation in SNMP::Info::FDP for details.

SNMP::Info::IEEE802_Bridge
    SNMP Interface to data available through the IEEE8021-Q-BRIDGE-MIB

    See documentation in SNMP::Info::IEEE802_Bridge for details.

SNMP::Info::IEEE802dot11
    IEEE802dot11-MIB. A collection of OIDs providing information about
    standards based 802.11 wireless devices.

    See documentation in SNMP::Info::IEEE802dot11 for details.

SNMP::Info::IEEE802dot3ad
    SNMP Interface to IEEE Aggregated Links. IEEE8023-LAG-MIB

    See documentation in SNMP::Info::IEEE802dot3ad for details.

SNMP::Info::IPv6
    SNMP Interface for obtaining configured IPv6 addresses and mapping
    IPv6 addresses to MAC addresses and interfaces, using information
    from IP-MIB, IPV6-MIB and/or CISCO-IETF-IP-MIB.

    See documentation in SNMP::Info::IPv6 for details.

SNMP::Info::LLDP
    LLDP-MIB, LLDP-EXT-DOT1-MIB, and LLDP-EXT-DOT3-MIB. Link Layer
    Discovery Protocol (LLDP) Support.

    See documentation in SNMP::Info::LLDP for details.

SNMP::Info::MAU
    MAU-MIB (RFC2668). Some Layer2 devices use this for extended
    Ethernet (Medium Attachment Unit) interface information.

    See documentation in SNMP::Info::MAU for details.

SNMP::Info::MRO
    Method resolution introspection for SNMP::Info

    See documentation in SNMP::Info::MRO for details.

SNMP::Info::NortelStack
    S5-AGENT-MIB, S5-CHASSIS-MIB.

    See documentation in SNMP::Info::NortelStack for details.

SNMP::Info::PortAccessEntity
    IEEE8021-PAE-MIB

    See documentation in SNMP::Info::PortAccessEntity for details.

SNMP::Info::PowerEthernet
    POWER-ETHERNET-MIB

    See documentation in SNMP::Info::PowerEthernet for details.

SNMP::Info::RapidCity
    RAPID-CITY. Inherited by Avaya switches for duplex and VLAN
    information.

    See documentation in SNMP::Info::RapidCity for details.

SNMP::Info::SONMP
    SynOptics Network Management Protocol (SONMP) SYNOPTICS-ROOT-MIB,
    S5-ETH-MULTISEG-TOPOLOGY-MIB. Inherited by
    Avaya/Nortel/Bay/Synoptics switches and hubs.

    See documentation in SNMP::Info::SONMP for details.

Device Subclasses These subclasses inherit from one or more classes to provide a common interface to data obtainable from network devices.

All the required MIB files are included in the netdisco-mib package.
(See Above).

SNMP::Info::Layer1
    Generic Layer1 Device subclass.

    See documentation in SNMP::Info::Layer1 for details.

    SNMP::Info::Layer1::Allied
        Subclass for Allied Telesis Repeaters / Hubs.

        Requires ATI-MIB

        See documentation in SNMP::Info::Layer1::Allied for details.

    SNMP::Info::Layer1::Asante
        Subclass for Asante 1012 Hubs.

        Requires ASANTE-HUB1012-MIB

        See documentation in SNMP::Info::Layer1::Asante for details.

    SNMP::Info::Layer1::Bayhub
        Subclass for Nortel/Bay hubs. This includes System 5000, 100
        series, 200 series, and probably more.

        See documentation in SNMP::Info::Layer1::Bayhub for details.

    SNMP::Info::Layer1::Cyclades
        Subclass for Cyclades/Avocent terminal servers.

        See documentation in SNMP::Info::Layer1::Cyclades for details.

    SNMP::Info::Layer1::S3000
        Subclass for Bay/Synoptics hubs. This includes System 3000,
        281X, and probably more.

        See documentation in SNMP::Info::Layer1::S3000 for details.

SNMP::Info::Layer2
    Generic Layer2 Device subclass.

    See documentation in SNMP::Info::Layer2 for details.

    SNMP::Info::Layer2::3Com
        Subclass for L2 3Com Switches.

        See documentation in SNMP::Info::Layer2::3Com for details.

    SNMP::Info::Layer2::Adtran
        Subclass for Adtran devices.

        See documentation in SNMP::Info::Layer2::Adtran for details.

    SNMP::Info::Layer2::Aerohive
        Subclass for Aerohive / Extreme access points.

        See documentation in SNMP::Info::Layer2::Aerohive for details.

    SNMP::Info::Layer2::Airespace
        Subclass for Cisco (Airespace) wireless controllers.

        See documentation in SNMP::Info::Layer2::Airespace for details.

    SNMP::Info::Layer2::Aironet
        Class for Cisco Aironet wireless devices that run IOS. See also
        SNMP::Info::Layer3::Aironet for Aironet devices that don't run
        IOS.

        See documentation in SNMP::Info::Layer2::Aironet for details.

    SNMP::Info::Layer2::Allied
        Allied Telesis switches.

        See documentation in SNMP::Info::Layer2::Allied for details.

    SNMP::Info::Layer2::Atmedia
        Subclass for atmedia encryptors.

        See documentation in SNMP::Info::Layer2::Atmedia for details.

    SNMP::Info::Layer2::Baystack
        Subclass for Avaya/Nortel/Bay Ethernet Switch/Baystack switches.
        This includes 303, 304, 350, 380, 410, 420, 425, 450, 460, 470
        series, 2500 series, 4000 series, 5000 series, Business Ethernet
        Switch (BES), Business Policy Switch (BPS), VSP 7000 series, and
        probably others.

        See documentation in SNMP::Info::Layer2::Baystack for details.

    SNMP::Info::Layer2::C1900
        Subclass for Cisco Catalyst 1900 and 1900c Devices running
        CatOS.

        See documentation in SNMP::Info::Layer2::C1900 for details.

    SNMP::Info::Layer2::C2900
        Subclass for Cisco Catalyst 2900, 2950, 3500XL, and 3548 devices
        running IOS.

        See documentation in SNMP::Info::Layer2::C2900 for details.

    SNMP::Info::Layer2::Catalyst
        Subclass for Cisco Catalyst switches running CatOS. These
        switches usually report a model number that starts with "wsc".
        Note that this class does not support everything that has the
        name Catalyst.

        See documentation in SNMP::Info::Layer2::Catalyst for details.

    SNMP::Info::Layer2::Centillion
        Subclass for Nortel/Bay Centillion and 5000BH ATM switches.

        See documentation in SNMP::Info::Layer2::Centillion for details.

    SNMP::Info::Layer2::Cisco
        Generic Cisco subclass for layer 2 devices that are not yet
        supported in more specific subclasses and the base layer 2 Cisco
        class for other device specific layer 2 Cisco classes.

        See documentation in SNMP::Info::Layer2::Cisco for details.

    SNMP::Info::Layer2::CiscoSB
        Subclass for Cisco's "Small Business" product line, acquired
        from Linksys. This currently comprises the Sx300/500 line of
        switches.

        See documentation in SNMP::Info::Layer2::CiscoSB for details.

    SNMP::Info::Layer2::Exinda
        Subclass for Exinda / GFI Network Orchestrator traffic shapers.

        See documentation in SNMP::Info::Layer2::Exinda for details.

    SNMP::Info::Layer2::Hirschmann
        Subclass for Hirschmann switches

        See documentation in SNMP::Info::Layer2::Hirschmann for details.

    SNMP::Info::Layer2::HP
        Subclass for more recent HP Procurve Switches.

        Requires HP-ICF-OID and ENTITY-MIB downloaded from HP.

        See documentation in SNMP::Info::Layer2::HP for details.

    SNMP::Info::Layer2::HP4000
        Subclass for older HP Procurve Switches

        Requires HP-ICF-OID and ENTITY-MIB downloaded from HP.

        See documentation in SNMP::Info::Layer2::HP4000 for details.

    SNMP::Info::Layer2::HPVC
        Subclass for HP Virtual Connect Switches

        See documentation in SNMP::Info::Layer2::HPVC for details.

    SNMP::Info::Layer2::Kentrox
        Class for Kentrox DataSMART DSU/CSU.

        See documentation in SNMP::Info::Layer2::Kentrox for details.

    SNMP::Info::Layer2::N2270
        Subclass for Nortel 2270 wireless switches.

        See documentation in SNMP::Info::Layer2::N2270 for details.

    SNMP::Info::Layer2::NAP222x
        Subclass for Nortel 222x series wireless access points.

        See documentation in SNMP::Info::Layer2::NAP222x for details.

    SNMP::Info::Layer2::Netgear
        Subclass for Netgear switches

        See documentation in SNMP::Info::Layer2::Netgear for details.

    SNMP::Info::Layer2::Nexans
        Subclass for Nexans switches

        See documentation in SNMP::Info::Layer2::Nexans for details.

    SNMP::Info::Layer2::NWSS2300
        SNMP Interface to Avaya (Trapeze) Wireless Controllers

        See documentation in SNMP::Info::Layer2::NWSS2300 for details.

    SNMP::Info::Layer2::Orinoco
        Subclass for Orinoco/Proxim wireless access points.

        See documentation in SNMP::Info::Layer2::Orinoco for details.

    SNMP::Info::Layer2::Trapeze
        SNMP Interface to Juniper (Trapeze) Wireless Controllers

        See documentation in SNMP::Info::Layer2::Trapeze for details.

    SNMP::Info::Layer2::Sixnet
        SNMP Interface to Sixnet industrial switches

        See documentation in SNMP::Info::Layer2::Sixnet for details.

    SNMP::Info::Layer2::Ubiquiti
        SNMP Interface to Ubiquiti Access Points and other devices

        See documentation in SNMP::Info::Layer2::Ubiquiti for details.

    SNMP::Info::Layer2::ZyXEL_DSLAM
        Zyxel DSLAMs. Need I say more?

        See documentation in SNMP::Info::Layer2::ZyXEL_DSLAM for
        details.

SNMP::Info::Layer3
    Generic Layer3 and Layer2+3 Device subclass.

    See documentation in SNMP::Info::Layer3 for details.

    SNMP::Info::Layer3::Aironet
        Subclass for Cisco Aironet wireless access points (AP) not
        running IOS. These are usually older devices.

        Note SNMP::Info::Layer2::Aironet

        See documentation in SNMP::Info::Layer3::Aironet for details.

    SNMP::Info::Layer3::AlcatelLucent
        Alcatel-Lucent OmniSwitch Class.

        See documentation in SNMP::Info::Layer3::AlcatelLucent for
        details.

    SNMP::Info::Layer3::AlteonAD
        Subclass for Radware Alteon Series ADC switches and Nortel
        BladeCenter Layer2-3 GbE Switch Modules.

        See documentation in SNMP::Info::Layer3::AlteonAD for details.

    SNMP::Info::Layer3::Altiga
        See documentation in SNMP::Info::Layer3::Altiga for details.

    SNMP::Info::Layer3::Meraki
        See documentation in SNMP::Info::Layer3::Meraki for details.

    SNMP::Info::Layer3::Arista
        See documentation in SNMP::Info::Layer3::Arista for details.

    SNMP::Info::Layer3::Aruba
        Subclass for Aruba wireless switches.

        See documentation in SNMP::Info::Layer3::Aruba for details.

    SNMP::Info::Layer3::ArubaCX
        SNMP Interface to L3 Devices running ArubaOS-CX

        See documentation in SNMP::Info::Layer3::ArubaCX for details.

    SNMP::Info::Layer3::BayRS
        Subclass for Avaya/Nortel/Bay Multiprotocol/BayRS routers. This
        includes BCN, BLN, ASN, ARN, AN, 2430, and 5430 routers.

        See documentation in SNMP::Info::Layer3::BayRS for details.

    SNMP::Info::Layer3::BlueCoatSG
        Subclass for BlueCoat SG series proxy devices.

        See documentation in SNMP::Info::Layer3::BlueCoatSG for details.

    SNMP::Info::Layer3::C1300
        See documentation in SNMP::Info::Layer3::C1300 for details.

    SNMP::Info::Layer3::C3550
        Subclass for Cisco Catalyst 3550,3540,3560 2/3 switches running
        IOS.

        See documentation in SNMP::Info::Layer3::C3550 for details.

    SNMP::Info::Layer3::C4000
        This class covers Catalyst 4000s and 4500s.

        See documentation in SNMP::Info::Layer3::C4000 for details.

    SNMP::Info::Layer3::C6500
        This class covers Catalyst 6500 series running CatOS or IOS, as
        well as Catalyst 2960, 2970, 3750 and 3850 series, including
        blade switches CBS30x0 and CBS31x0 series, all running IOS.

        See documentation in SNMP::Info::Layer3::C6500 for details.

    SNMP::Info::Layer3::CheckPoint
        Subclass for CheckPoint devices.

        See documentation in SNMP::Info::Layer3::CheckPoint for details.

    SNMP::Info::Layer3::Ciena
        Subclass for Ciena devices.

        See documentation in SNMP::Info::Layer3::Ciena for details.

    SNMP::Info::Layer3::Cisco
        This is a simple wrapper around layer 3 for IOS devices and the
        base layer 3 Cisco class for other device specific layer 3 Cisco
        classes.

        See documentation in SNMP::Info::Layer3::Cisco for details.

    SNMP::Info::Layer3::CiscoASA
        Subclass for Cisco Adaptive Security Appliances.

        See documentation in SNMP::Info::Layer3::CiscoASA for details.

    SNMP::Info::Layer3::CiscoFWSM
        Subclass for Cisco Firewall Services Modules.

        See documentation in SNMP::Info::Layer3::CiscoFWSM for details.

    SNMP::Info::Layer3::CiscoSwitch
        Base class for L3 Cisco switches. See documentation in
        SNMP::Info::Layer3::CiscoSwitch for details.

    SNMP::Info::Layer3::Contivity
        Subclass for Avaya/Nortel Contivity/VPN Routers.

        See documentation in SNMP::Info::Layer3::Contivity for details.

    SNMP::Info::Layer3::Cumulus
        Subclass for Cumulus Networks Routers.

        See documentation in SNMP::Info::Layer3::Cumulus for details.

    SNMP::Info::Layer3::Dell
        Subclass for Dell PowerConnect switches. The IBM BladeCenter
        Gigabit Ethernet Switch Module and some Linksys switches also
        use this module based upon MIB support.

        See documentation in SNMP::Info::Layer3::Dell for details.

    SNMP::Info::Layer3::DLink
        Subclass for DLink devices.

        See documentation in SNMP::Info::Layer3::DLink for details.

    SNMP::Info::Layer3::Enterasys
        Subclass for Enterasys devices.

        See documentation in SNMP::Info::Layer3::Enterasys for details.

    SNMP::Info::Layer3::ERX
        Subclass for Juniper ERX switches.

        See documentation in SNMP::Info::Layer3::ERX for details.

    SNMP::Info::Layer3::Extreme
        Subclass for Extreme Networks switches.

        See documentation in SNMP::Info::Layer3::Extreme for details.

    SNMP::Info::Layer3::ExtremeWing
        Subclass for Extreme WiNG APs.

        See documentation in SNMP::Info::Layer3::ExtremeWing for
        details.

    SNMP::Info::Layer3::F5
        Subclass for F5 devices.

        See documentation in SNMP::Info::Layer3::F5 for details.

    SNMP::Info::Layer3::Force10
        Subclass for Force10 devices.

        See documentation in SNMP::Info::Layer3::Force10 for details.

    SNMP::Info::Layer3::Fortinet
        Subclass for Fortinet devices.

        See documentation in SNMP::Info::Layer3::Fortinet for details.

    SNMP::Info::Layer3::Foundry
        Subclass for Brocade (Foundry) Network devices.

        See documentation in SNMP::Info::Layer3::Foundry for details.

    SNMP::Info::Layer3::Genua
        Subclass for Genua security devices.

        See documentation in SNMP::Info::Layer3::Genua for details.

    SNMP::Info::Layer3::H3C
        SNMP Interface to Layer 3 Devices, H3C & HP A-series.

        See documentation in SNMP::Info::Layer3::H3C for details.

    SNMP::Info::Layer3::HP9300
        Subclass for HP network devices which Foundry Networks was the
        Original Equipment Manufacturer (OEM) such as the HP ProCurve
        9300 and 6300 series.

        See documentation in SNMP::Info::Layer3::HP9300 for details.

    SNMP::Info::Layer3::Huawei
        SNMP Interface to Huawei Layer 3 switches and routers.

        See documentation in SNMP::Info::Layer3::Huawei for details.

    SNMP::Info::Layer3::IBMGbTor
        SNMP Interface to IBM Rackswitch (formerly Blade Network
        Technologies) network devices. Lenovo acquired these from IBM
        and is now selling them under the Lenovo brand.

        See documentation in SNMP::Info::Layer3::IBMGbTor for details.

    SNMP::Info::Layer3::Juniper
        Subclass for Juniper devices.

        See documentation in SNMP::Info::Layer3::Juniper for details.

    SNMP::Info::Layer3::Lantronix
        Subclass for Lantronix devices.

        See documentation in SNMP::Info::Layer3::Lantronix for details.

    SNMP::Info::Layer3::Lenovo
        Subclass for Lenovo switches running CNOS.

        See documentation in SNMP::Info::Layer3::Lenovo for details.

    SNMP::Info::Layer3::Microsoft
        Subclass for Generic Microsoft Routers running Microsoft Windows
        OS.

        See documentation in SNMP::Info::Layer3::Microsoft for details.

    SNMP::Info::Layer3::Mikrotik
        Subclass for Mikrotik devices running RouterOS.

        See documentation in SNMP::Info::Layer3::Mikrotik for details.

    SNMP::Info::Layer3::N1600
        Subclass for Avaya/Nortel Ethernet Routing Switch 1600 series.

        See documentation in SNMP::Info::Layer3::N1600 for details.

    SNMP::Info::Layer3::Netonix
        Subclass for Netonix switches.

        See documentation in SNMP::Info::Layer3::Netonix for details.

    SNMP::Info::Layer3::NetSNMP
        Subclass for host systems running Net-SNMP.

        See documentation in SNMP::Info::Layer3::NetSNMP for details.

    SNMP::Info::Layer3::Netscreen
        Subclass for Juniper NetScreen.

        See documentation in SNMP::Info::Layer3::Netscreen for details.

    SNMP::Info::Layer3::Nexus
        Subclass for Cisco Nexus devices running NX-OS.

        See documentation in SNMP::Info::Layer3::Nexus for details.

    SNMP::Info::Layer3::OneAccess
        Subclass for OneAccess routers.

        See documentation in SNMP::Info::Layer3::OneAccess for details.

    SNMP::Info::Layer3::PacketFront
        Subclass for PacketFront DRG series CPE.

        See documentation in SNMP::Info::Layer3::PacketFront for
        details.

    SNMP::Info::Layer3::PaloAlto
        Subclass for Palo Alto firewalls.

        See documentation in SNMP::Info::Layer3::PaloAlto for details.

    SNMP::Info::Layer3::Passport
        Subclass for Avaya/Nortel Ethernet Routing Switch/Passport 8000
        series, Accelar, and VSP 9000 series switches.

        See documentation in SNMP::Info::Layer3::Passport for details.

    SNMP::Info::Layer3::Pf
        Subclass for FreeBSD-Based Firewalls using Pf /Pf Sense

        See documentation in SNMP::Info::Layer3::Pf for details.

    SNMP::Info::Layer3::Pica8
        Subclass for Pica8 devices.

        See documentation in SNMP::Info::Layer3::Pica8 for details.

    SNMP::Info::Layer3::Redlion
        Subclass for redlion routers.

        See documentation in SNMP::Info::Layer3::Redlion for details.

    SNMP::Info::Layer3::SilverPeak
        Subclass for SilverPeak devices.

        See documentation in SNMP::Info::Layer3::SilverPeak for details.

    SNMP::Info::Layer3::Scalance
        Subclass for Siemens Scalance devices.

        See documentation in SNMP::Info::Layer3::Scalance for details.

    SNMP::Info::Layer3::SonicWALL
        Subclass for generic SonicWALL devices.

        See documentation in SNMP::Info::Layer3::SonicWALL for details.

    SNMP::Info::Layer3::Steelfusion
        Subclass for Riverbed Steelfusion WAN optimization appliances.

        See documentation in SNMP::Info::Layer3::Steelfusion for
        details.

    SNMP::Info::Layer3::Steelhead
        Subclass for Riverbed Steelhead WAN optimization appliances.

        See documentation in SNMP::Info::Layer3::Steelhead for details.

    SNMP::Info::Layer3::SteelheadEx
        Subclass for Riverbed SteelheadEx WAN optimization appliances.

        See documentation in SNMP::Info::Layer3::SteelheadEx for
        details.

    SNMP::Info::Layer3::Sun
        Subclass for Generic Sun Routers running SunOS.

        See documentation in SNMP::Info::Layer3::Sun for details.

    SNMP::Info::Layer3::Tasman
        Subclass for Avaya Secure Routers.

        See documentation in SNMP::Info::Layer3::Tasman for details.

    SNMP::Info::Layer3::Teltonika
        Subclass for Teltonika RUT9xx series routers.

        See documentation in SNMP::Info::Layer3::Teltonika for details.

    SNMP::Info::Layer3::Timetra
        Alcatel-Lucent SR Class.

        See documentation in SNMP::Info::Layer3::Timetra for details.

    SNMP::Info::Layer3::VyOS
        Subclass for VyOS routers.

        See documentation in SNMP::Info::Layer3::VyOS for details.

    SNMP::Info::Layer3::VMware
        Subclass for VMware ESXi hosts.

        See documentation in SNMP::Info::Layer3::VMware for details.

    SNMP::Info::Layer3::Whiterabbit
        Subclass for whiterabbit devices.

        See documentation in SNMP::Info::Layer3::Whiterabbit for
        details.

SNMP::Info::Layer7
    Generic Layer7 Devices.

    See documentation in SNMP::Info::Layer7 for details.

    SNMP::Info::Layer7::APC
        Subclass for APC UPS devices.

        See documentation in SNMP::Info::Layer7::APC for details.

    SNMP::Info::Layer7::Arbor
        Subclass for Arbor appliances.

        See documentation in SNMP::Info::Layer7::Arbor for details.

    SNMP::Info::Layer7::CiscoIPS
        Subclass for Cisco IPS devices.

        See documentation in SNMP::Info::Layer7::CiscoIPS for details.

    SNMP::Info::Layer7::Gigamon
        Subclass for Gigamon devices.

        See documentation in SNMP::Info::Layer7::Gigamon for details.

    SNMP::Info::Layer7::HWGroup
        Subclass for HW Group devices.

        See documentation in SNMP::Info::Layer7::HWGroup for details.

    SNMP::Info::Layer7::Liebert
        Subclass for Liebert devices.

        See documentation in SNMP::Info::Layer7::Liebert for details.

    SNMP::Info::Layer7::Neoteris
        Subclass for Pulse Secure / Juniper SSL VPN appliances.

        See documentation in SNMP::Info::Layer7::Neoteris for details.

    SNMP::Info::Layer7::Netscaler
        Subclass for Citrix Netscaler appliances.

        See documentation in SNMP::Info::Layer7::Netscaler for details.

Thanks Thanks for testing and coding help (in no particular order) to : Alexander Barthel, Andy Ford, Alexander Hartmaier, Andrew Herrick, Alex Kramarov, Bernhard Augenstein, Bradley Baetz, Brian Chow, Brian Wilson, Carlos Vicente, Dana Watanabe, David Pinkoski, David Sieborger, Douglas McKeown, Greg King, Ivan Auger, Jean-Philippe Luiggi, Jeroen van Ingen, Justin Hunter, Kent Hamilton, Matthew Tuttle, Michael Robbert, Mike Hunter, Nicolai Petri, Ralf Gross, Robert Kerr, Nick Nauwelaerts and people listed on the Netdisco README!

USAGE Constructor new() Creates a new object and connects via SNMP::Session.

    Always returns an SNMP::Info instance, and you should always check
    for error() as in SYNOPSIS above to be sure of success.

    Will take a bare list of key/value options but we recommend a HASH
    ref as in the example below and SYNOPSIS, to catch syntax errors.

     my $info = SNMP::Info->({ 'Debug'             => 1,
                               'AutoSpecify'       => 1,
                               'BigInt'            => 1,
                               'BulkWalk'          => 1,
                               'BulkRepeaters'     => 20,
                               'LoopDetect'        => 1,
                               'IgnoreNetSNMPConf' => 1,
                               'DestHost'          => 'myrouter',
                               'Community'         => 'public',
                               'Version'           => 2,
                               'MibDirs'           => ['dir1','dir2','dir3'],
                            });

    SNMP::Info Specific Arguments :

    AutoSpecify
        Returns an object of a more specific device class

        (default 0, which means "off")

    BigInt
        Return Math::BigInt objects for 64 bit counters. Sets on a
        global scope, not object.

        (default 0, which means "off")

    BulkWalk
        Set to 0 to turn off BULKWALK commands for SNMPv2 connections.

        Note that BULKWALK is turned off for Net-SNMP versions 5.1.x
        because of a bug.

        (default 1, which means "on")

    BulkRepeaters
        Set number of MaxRepeaters for BULKWALK operation. See "perldoc
        SNMP" -> bulkwalk() for more info.

        (default 20)

    LoopDetect
        Detects looping during getnext table column walks by comparing
        IIDs for each instance. A loop is detected if the same IID is
        seen more than once and the walk is aborted. Note: This will not
        detect loops during a bulkwalk operation, Net-SNMP's internal
        bulkwalk function must detect the loop.

        Set to 0 to turn off loop detection.

        (default 1, which means "on")

    IgnoreNetSNMPConf
        Net-SNMP version 5.0 and higher read configuration files,
        snmp.conf or snmp.local.conf, from /etc/snmp, /usr/share/snmp,
        /usr/lib(64)/snmp, or $HOME/.snmp and uses those settings to
        automatically parse MIB files, etc.

        Set to 1 "on" to ignore Net-SNMP configuration files by
        overriding the "SNMPCONFPATH" environmental variable during
        object initialization. Note: MibDirs must be defined or Net-SNMP
        will not be able to load MIBs and initialize the object.

        (default 0, which means "off")

    Debug
        Prints Lots of debugging messages. Pass 2 to print even more
        debugging messages.

        (default 0, which means "off")

    DebugSNMP
        Set $SNMP::debugging level for Net-SNMP.

        See SNMP for more details.

    MibDirs
        Array ref to list of directories in which to look for MIBs. Note
        this will be in addition to the ones setup in snmp.conf at the
        system level.

        (default use net-snmp settings only)

    RetryNoSuch
        When using SNMP Version 1, try reading values even if they come
        back as "no such variable in this MIB". Set to false if so
        desired. This feature lets you read SNMPv2 data from an SNMP
        version 1 connection, and should probably be left on.

        (default 1, which means "on")

    Session
        SNMP::Session object to use instead of connecting on own.

        (default creates session automatically)

    Offline
        Causes SNMP::Info to avoid network activity and return data only
        from its cache. If you ask for something not in the cache, an
        error is thrown. See also the cache() and offline() methods.

        (default 0, which means "online")

    Cache
        Pass in a HashRef to prime the cache of retrieved data. Useful
        for creating an instance in "Offline" mode from a previously
        dumped cache. See also the cache() method to retrieve a cache
        after running actual queries.

    OTHER
        All other arguments are passed to SNMP::Session.

        See SNMP::Session for a list of other possible arguments.

    A Note about the wrong Community string or wrong SNMP Version:

    If a connection is using the wrong community string or the wrong
    SNMP version, the creation of the object will not fail. The device
    still answers the call on the SNMP port, but will not return
    information. Check the error() method after you create the device
    object to see if there was a problem in connecting.

    A note about SNMP Versions :

    Some older devices don't support SNMP version 2, and will not return
    anything when a connection under Version 2 is attempted.

    Some newer devices will support Version 1, but will not return all
    the data they might have if you had connected under Version 1.

    When trying to get info from a new device, you may have to try
    version 2 and then fallback to version 1.

update()
    Replace the existing session with a new one with updated values,
    without re-identifying the device. The only supported changes are to
    Community or Context.

    Clears the object cache.

    This is useful, e.g., when a device supports multiple contexts (via
    changes to the Community string, or via the SNMPv3 Context
    parameter), but a context that you want to access does not support
    the objects (e.g., "sysObjectID", "sysDescr") that we use to
    identify the device.

Data is Cached Methods and subroutines requesting data from a device will only load the data once, and then return cached versions of that data.

Run $info->load_METHOD() where method is something like 'i_name' to
reload data from a method.

Run $info->clear_cache() to clear the cache to allow reload of both
globals and table methods.

The cache can be retrieved or set using the $info->cache() method. This
works together with the "Offline" option.

Object Scalar Methods These are for package related data, not directly supplied from SNMP.

$info->clear_cache()
    Clears the cached data. This includes GLOBALS data and TABLE METHOD
    data.

$info->debug(1)
    Returns current debug status, and optionally toggles debugging info
    for this object.

$info->offline([1|0])
    Returns if offline mode is currently turned on for this object.

    Optionally sets the Offline parameter.

$info->cache([new_cache])
    Returns a HashRef of all cached data in this object. There will be a
    "store" key for table data and then one key for each leaf.

    Optionally sets the cache parameters if passed a HashRef.

$info->bulkwalk([1|0])
    Returns if bulkwalk is currently turned on for this object.

    Optionally sets the bulkwalk parameter.

$info->loopdetect([1|0])
    Returns if loopdetect is currently turned on for this object.

    Optionally sets the loopdetect parameter.

$info->device_type()
    Returns the Subclass name for this device. "SNMP::Info" is returned
    if no more specific class is available.

    First the device is checked for Layer 3 support and a specific
    subclass, then Layer 2 support and subclasses are checked.

    This means that Layer 2 / 3 switches and routers will fall under the
    SNMP::Info::Layer3 subclasses.

    If the device still can be connected to via SNMP::Info, then
    SNMP::Info is returned.

$info->error(no_clear)
    Returns Error message if there is an error, or undef if there is
    not.

    Reading the error will clear the error unless you set the no_clear
    flag.

$info->has_layer(3)
    Returns non-zero if the device has the supplied layer in the OSI
    Model

    Returns if the device doesn't support the layers() call.

$info->snmp_comm()
    Returns SNMP Community string used in connection.

$info->snmp_ver()
    Returns SNMP Version used for this connection

$info->specify()
    Returns an object of a more-specific subclass.

     my $info = new SNMP::Info(...);
     # Returns more specific object type
     my $specific = $info->specify();

    Usually this method is called internally from new(AutoSpecify => 1)

    See device_type() entry for how a subclass is chosen.

$info->cisco_comm_indexing()
    Returns 0. Is an overridable method used for vlan indexing for snmp
    calls on certain Cisco devices.

    See
    <ftp://ftp.cisco.com/pub/mibs/supportlists/wsc5000/wsc5000-community
    Indexing.html>

GLOBALS (Scalar Methods) These are methods to return scalar data from RFC1213.

Some subset of these is probably available for any network device that
speaks SNMP.

$info->uptime()
    Uptime in hundredths of seconds since device became available.

    ("sysUpTime")

$info->contact()
    ("sysContact")

$info->name()
    ("sysName")

$info->location()
    ("sysLocation")

$info->layers()
    This returns a binary encoded string where each digit represents a
    layer of the OSI model served by the device.

        eg: 01000010  means layers 2 (physical) and 7 (Application)
                      are served.

    Note: This string is 8 digits long.

    See $info->has_layer()

    ("sysServices")

$info->ports()
    Number of interfaces available on this device.

    Not too useful as the number of SNMP interfaces usually does not
    correspond with the number of physical ports

    ("ifNumber")

$info->ipforwarding()
    The indication of whether the entity is acting as an IP gateway

    Returns either forwarding or not-forwarding

    ("ipForwarding")

Table Methods Each of these methods returns a hash_reference to a hash keyed on the interface index in SNMP.

Example : $info->interfaces() might return

    { '1.12' => 'FastEthernet/0',
      '2.15' => 'FastEthernet/1',
      '9.99' => 'FastEthernet/2'
    }

The key is what you would see if you were to do an snmpwalk, and in some
cases changes between reboots of the network device.

Partial Table Fetches If you want to get only a part of an SNMP table or a single instance from the table and you know the IID for the part of the table that you want, you can specify it in the call:

    $local_routes = $info->ipr_route('192.168.0');

This will only fetch entries in the table that start with 192.168.0,
which in this case are routes on the local network.

Remember that you must supply the partial IID (a numeric OID).

Partial table results are not cached.

Interface Information $info->interfaces() This methods is overridden in each subclass to provide a mapping between the Interface Table Index (iid) and the physical port name.

$info->if_ignore()
    Returns a reference to a hash where key values that exist are
    interfaces to ignore.

    Ignored interfaces are ones that are usually not physical ports or
    Virtual Lans (VLANs) such as the Loopback interface, or the CPU
    interface.

$info->bulkwalk_no()
    Returns 0. Is an overridable method used for turn off bulkwalk for
    the device class.

$info->i_index()
    Default SNMP IID to Interface index.

    ("ifIndex")

$info->i_description()
    Description of the interface. Usually a little longer single word
    name that is both human and machine friendly. Not always.

    ("ifDescr")

$info->i_type()
    Interface type, such as Vlan, Ethernet, Serial

    ("ifType")

$info->i_mtu()
    INTEGER. Interface MTU value.

    ("ifMtu")

$info->i_speed()
    Speed of the link, human format. See munge_speed() later in document
    for details.

    ("ifSpeed", "ifHighSpeed" if necessary)

$info->i_speed_raw()
    Speed of the link in bits per second without munging. If
    i_speed_high is available it will be used and multiplied by
    1_000_000.

    ("ifSpeed", "ifHighSpeed" if necessary)

$info->i_speed_high()
    Speed of a high-speed link, human format. See munge_highspeed()
    later in document for details. You should not need to call this
    directly, as i_speed() will call it if it needs to.

    ("ifHighSpeed")

$info->i_mac()
    MAC address of the interface. Note this is just the MAC of the port,
    not anything connected to it.

    ("ifPhysAddress")

$info->i_up()
    Link Status of the interface. Typical values are 'up' and 'down'.

    ("ifOperStatus")

$info->i_up_admin()
    Administrative status of the port. Typical values are 'enabled' and
    'disabled'.

    ("ifAdminStatus")

$info->i_lastchange()
    The value of "sysUpTime" when this port last changed states
    (up,down).

    ("ifLastChange")

$info->i_name()
    Interface Name field. Supported by a smaller subset of devices, this
    fields is often human set.

    ("ifName")

$info->i_alias()
    Interface Name field. For certain devices this is a more human
    friendly form of i_description(). For others it is a human set field
    like i_name().

    ("ifAlias")

Interface Statistics $info->i_octet_in(), $info->i_octet_out(), $info->i_octet_in64(), $info->i_octet_out64() Bandwidth.

    Number of octets sent/received on the interface including framing
    characters.

    64 bit version may not exist on all devices.

    NOTE: To manipulate 64 bit counters you need to use Math::BigInt,
    since the values are too large for a normal Perl scalar. Set the
    global $SNMP::Info::BIGINT to 1 , or pass the BigInt value to new()
    if you want SNMP::Info to do it for you.

    ("ifInOctets") ("ifOutOctets") ("ifHCInOctets") ("ifHCOutOctets")

$info->i_errors_in(), $info->i_errors_out()
    Number of packets that contained an error preventing delivery. See
    "IF-MIB" for more info.

    ("ifInErrors") ("ifOutErrors")

$info->i_pkts_ucast_in(), $info->i_pkts_ucast_out(),
$info->i_pkts_ucast_in64(), $info->i_pkts_ucast_out64()
    Number of packets not sent to a multicast or broadcast address.

    64 bit version may not exist on all devices.

    ("ifInUcastPkts") ("ifOutUcastPkts") ("ifHCInUcastPkts")
    ("ifHCOutUcastPkts")

$info->i_pkts_nucast_in(), $info->i_pkts_nucast_out(),
    Number of packets sent to a multicast or broadcast address.

    These methods are deprecated by i_pkts_multi_in() and
    i_pkts_bcast_in() according to "IF-MIB". Actual device usage may
    vary.

    ("ifInNUcastPkts") ("ifOutNUcastPkts")

$info->i_pkts_multi_in() $info->i_pkts_multi_out(),
$info->i_pkts_multi_in64(), $info->i_pkts_multi_out64()
    Number of packets sent to a multicast address.

    64 bit version may not exist on all devices.

    ("ifInMulticastPkts") ("ifOutMulticastPkts") ("ifHCInMulticastPkts")
    ("ifHCOutMulticastPkts")

$info->i_pkts_bcast_in() $info->i_pkts_bcast_out(),
$info->i_pkts_bcast_in64() $info->i_pkts_bcast_out64()
    Number of packets sent to a broadcast address on an interface.

    64 bit version may not exist on all devices.

    ("ifInBroadcastPkts") ("ifOutBroadcastPkts") ("ifHCInBroadcastPkts")
    ("ifHCOutBroadcastPkts")

$info->i_discards_in() $info->i_discards_out()
    "The number of inbound packets which were chosen to be discarded
    even though no errors had been detected to prevent their being
    deliverable to a higher-layer protocol. One possible reason for
    discarding such a packet could be to free up buffer space."
    ("IF-MIB")

    ("ifInDiscards") ("ifOutDiscards")

$info->i_bad_proto_in()
    "For packet-oriented interfaces, the number of packets received via
    the interface which were discarded because of an unknown or
    unsupported protocol. For character-oriented or fixed-length
    interfaces that support protocol multiplexing the number of
    transmission units received via the interface which were discarded
    because of an unknown or unsupported protocol. For any interface
    that does not support protocol multiplexing, this counter will
    always be 0."

    ("ifInUnknownProtos")

$info->i_qlen_out()
    "The length of the output packet queue (in packets)."

    ("ifOutQLen")

$info->i_specific()
    See "IF-MIB" for full description

    ("ifSpecific")

IPv4 Address Table Each entry in this table is an IPv4 address in use on this device. Usually this is implemented in Layer3 Devices. These methods try the deprecated IPv4 address table "IP-MIB::ipAddrTable" first due to its prevalence and will try the current "IP-MIB::ipAddressTable" if it doesn't return any results. "IP-MIB::ipAddressTable" results are filtered to only return IPv4 unicast addresses and modified to match the return format of the older table for backwards compatibility.

See documentation in SNMP::Info::IPv6 for IPv6 Address Table.

$info->ip_index()
    Maps the IPv4 addresses to the interface index

    ("ipAdEntIfIndex") or filtered and index modified
    ("ipAddressIfIndex")

$info->ip_table()
    Maps the Table to the IPv4 address

    ("ipAdEntAddr") or address extracted from ("ipAddressIfIndex")

$info->ip_netmask()
    Gives netmask setting for IPv4 table entry.

    ("ipAdEntNetMask") or netmask calculated from ("ipAddressPrefix")

$info->ip_broadcast()
    Gives the value of the least-significant bit in the IPv4 broadcast
    address either 1 or 0.

    ("ipAdEntBcastAddr"), there is no equivalent from the
    "IP-MIB::ipAddressTable"

IP Routing Table $info->ipr_route() The route in question. A value of 0.0.0.0 is the default gateway route.

    ("ipRouteDest")

$info->ipr_if()
    The interface (IID) that the route is on. Use interfaces() to map.

    ("ipRouteIfIndex")

$info->ipr_1()
    Primary routing metric for this route.

    ("ipRouteMetric1")

$info->ipr_2()
    If metrics are not used, they should be set to -1

    ("ipRouteMetric2")

$info->ipr_3()
    ("ipRouteMetric3")

$info->ipr_4()
    ("ipRouteMetric4")

$info->ipr_5()
    ("ipRouteMetric5")

$info->ipr_dest()
    From RFC1213:

      "The IP address of the next hop of this route.
      (In the case of a route bound to an interface
      which is realized via a broadcast media, the value
      of this field is the agent's IP address on that
      interface.)"

    ("ipRouteNextHop")

$info->ipr_type()
    From RFC1213:

        other(1),        -- none of the following
        invalid(2),      -- an invalidated route
                         -- route to directly
        direct(3),       -- connected (sub-)network
                         -- route to a non-local
        indirect(4)      -- host/network/sub-network

          "The type of route.  Note that the values
          direct(3) and indirect(4) refer to the notion of
          direct and indirect routing in the IP
          architecture.

          Setting this object to the value invalid(2) has
          the effect of invalidating the corresponding entry
          in the ipRouteTable object.  That is, it
          effectively disassociates the destination
          identified with said entry from the route
          identified with said entry.  It is an
          implementation-specific matter as to whether the
          agent removes an invalidated entry from the table.
          Accordingly, management stations must be prepared
          to receive tabular information from agents that
          corresponds to entries not currently in use.
          Proper interpretation of such entries requires
          examination of the relevant ipRouteType object."

    ("ipRouteType")

$info->ipr_proto()
    From RFC1213:

        other(1),       -- none of the following
                        -- non-protocol information,
                        -- e.g., manually configured
        local(2),       -- entries
                        -- set via a network
        netmgmt(3),     -- management protocol
                        -- obtained via ICMP,
        icmp(4),        -- e.g., Redirect
                        -- the remaining values are
                        -- all gateway routing
                        -- protocols
        egp(5),
        ggp(6),
        hello(7),
        rip(8),
        is-is(9),
        es-is(10),
        ciscoIgrp(11),
        bbnSpfIgp(12),
        ospf(13),
        bgp(14)

    ("ipRouteProto")

$info->ipr_age()
    Seconds since route was last updated or validated.

    ("ipRouteAge")

$info->ipr_mask()
    Subnet Mask of route. 0.0.0.0 for default gateway.

    ("ipRouteMask")

$info->ipr_info()
    Reference to MIB definition specific to routing protocol.

    ("ipRouteInfo")

Topology Information Based upon the manufacturer and software version devices may support some combination of Layer 2 topology protocol information. SNMP::Info supports querying Link Layer Discovery Protocol (LLDP), Cisco Discovery Protocol (CDP), SynOptics/Bay/Nortel/Avaya Network Management Protocol (SONMP), Foundry/Brocade Discovery Protocol (FDP), Extreme Discovery Protocol (EDP), and Alcatel Mapping Adjacency Protocol (AMAP).

For protocol specific information and implementation:

AMAP: See SNMP::Info::AMAP for details.
CDP: See SNMP::Info::CDP for details.
EDP: See SNMP::Info::EDP for details.
FDP: See SNMP::Info::FDP for details.
LLDP: See SNMP::Info::LLDP for details.
SONMP: See SNMP::Info::SONMP for details.

Topology Capabilities $info->has_topo() Reports Layer 2 topology protocols which are supported and running on a device.

    Returns either a reference to an array of protocols, possible values
    being: "lldp", "cdp", "sonmp", "fdp", "edp", "amap" or "undef" if no
    protocols are supported or running.

Common Topology Table Information The common topology table methods below will query the device for information from the specified topology protocols and return a single hash combining all information. As a result, there may be identical topology information returned from the two protocols causing duplicate entries. It is the calling program's responsibility to identify any duplicate entries and remove duplicates if necessary. If it is necessary to understand which protocol provided the information, utilize the protocol specific methods directly rather than the generic methods.

The methods support partial table fetches by providing a partial as the
first argument.

If a reference to an array is provided as the second argument, those
protocols will be queried for information. The supported array values
are: "lldp", "cdp", "sonmp", "fdp", "edp", "amap".

If nothing is passed in as the second argument, the methods will call
has_topo() to determine supported and running topology protocols on the
device.

$info->c_ip(partial, topology_protocol_arrayref)
    Returns reference to hash. Key: iid, Value: remote IPv4 address

    If multiple entries exist with the same local port, c_if(), with the
    same IPv4 address, c_ip(), it may be a duplicate entry.

    If multiple entries exist with the same local port, c_if(), with
    different IPv4 addresses, c_ip(), there is either a device in
    between two or more devices utilizing a different topology protocol
    or multiple devices which are not directly connected.

    Use the protocol specific methods to dig deeper.

$info->c_if(partial, topology_protocol_arrayref)
    Returns reference to hash. Key: iid, Value: local device port
    (interfaces)

$info->c_port(partial, topology_protocol_arrayref)
    Returns reference to hash. Key: iid, Value: remote port (interfaces)

$info->c_id(partial, topology_protocol_arrayref)
    Returns reference to hash. Key: iid, Value: string value used to
    identify the chassis component associated with the remote system.

    Note: SONMP does not return this information.

$info->c_platform(partial, topology_protocol_arrayref)
    Returns reference to hash. Key: iid, Value: Remote Device Type

    Note: EDP does not provide this information. LLDP uses
    ("lldpRemSysDesc") or "lldp_rem_sysname" as the closest match.

$info->c_cap(partial, topology_protocol_arrayref)
    Returns reference to hash of arrays. Key: iid, Value: Array of
    capabilities supported by the device. See the specific protocol
    class for string values which could be elements within the array.

    Note: Only CDP and LLDP support this method.

SETTING DATA VIA SNMP This section explains how to use SNMP::Info to do SNMP Set operations.

$info->set_METHOD($value)
    Sets the global METHOD to value. Assumes that iid is .0

    Returns if failed, or the return value from SNMP::Session::set()
    (snmp_errno)

     $info->set_location("Here!");

$info->set_METHOD($value,$iid)
    Table Methods. Set iid of method to value.

    Returns if failed, or the return value from SNMP::Session::set()
    (snmp_errno)

     # Disable a port administratively
     my %if_map = reverse %{$info->interfaces()}
     $info->set_i_up_admin('down', $if_map{'FastEthernet0/0'})
        or die "Couldn't disable the port. ",$info->error(1);

NOTE: You must be connected to your device with a "ReadWrite" community
string in order for set operations to work.

NOTE: This will only set data listed in %FUNCS and %GLOBALS. For data
acquired from overridden methods (subroutines) specific set_METHOD()
subroutines will need to be added if they haven't been already.

Quiet Mode SNMP::Info will not chirp anything to STDOUT unless there is a serious error (in which case it will probably die).

To get lots of debug info, set the Debug flag when calling new() or call
$info->debug(1);

When calling a method check the return value. If the return value is
undef then check $info->error()

Beware, calling $info->error() clears the error.

 my $name = $info->name() or die "Couldn't get sysName!" . $name->error();

EXTENDING SNMP::INFO To support a new class (vendor or platform) of device, add a Perl package with the data structures and methods listed below.

If this seems a little scary, then the SNMP::Info developers are usually
happy to accept the SNMP data from your device and make an attempt at
the class themselves. Usually a "beta" release will go to CPAN for you
to verify the implementation.

Gathering MIB data for SNMP::Info Developers The preference is to open a pull request in the github project. This allows all developers to have visibility into the request. Please include pointers to the applicable platform MIBs. For development we will need an "snmpwalk" of the device. There is a tool now included in the SNMP::Info distribution to help with this task, although you'll most likely need to download the distribution from CPAN as it's included in the ""contrib/util"" directory.

The utility is named "make_snmpdata.pl". Run it with a command line
like:

 ./make_snmpdata.pl -c community -i -d device_ip \
  -m /home/netdisco-mibs/rfc:/home/netdisco-mibs/net-snmp:/home/netdisco-mibs/dir3 \
  SNMPv2-MIB IF-MIB EtherLike-MIB BRIDGE-MIB Q-BRIDGE-MIB ENTITY-MIB \
  POWER-ETHERNET-MIB IPV6-MIB LLDP-MIB DEVICE-SPECIFIC-MIB-NAME(s) > output.txt

This will print to the file every MIB entry with data in a format that
the developers can use to emulate read operations without needing access
to the device. Preference would be to mask any sensitive data in the
output, zip the file, and attach it to the github pull request. However,
if you do not feel comfortable uploading the output to the tracker you
could e-mail it to the developer that has claimed the ticket.

Data Structures required in new Subclass A class inheriting this class must implement these data structures :

$INIT
    Used to flag if the MIBs have been loaded yet.

%GLOBALS
    Contains a hash in the form ( method_name => SNMP MIB leaf name )
    These are scalar values such as name, uptime, etc.

    To resolve MIB leaf name conflicts between private MIBs, you may
    prefix the leaf name with the MIB replacing each - (dash) and :
    (colon) with an _ (underscore). For example,
    ALTEON_TIGON_SWITCH_MIB__agSoftwareVersion would be used as the hash
    value instead of the net-snmp notation
    ALTEON-TIGON-SWITCH-MIB::agSoftwareVersion.

    When choosing the name for the methods, be aware that other new Sub
    Modules might inherit this one to get it's features. Try to choose a
    prefix for methods that will give it's own name space inside the
    SNMP::Info methods.

%FUNCS
    Contains a hash in the form ( method_name => SNMP MIB leaf name)
    These are table entries, such as the "ifIndex"

    To resolve MIB leaf name conflicts between private MIBs, you may
    prefix the leaf name with the MIB replacing each - (dash) and :
    (colon) with an _ (underscore). For example,
    ALTEON_TS_PHYSICAL_MIB__agPortCurCfgPortName would be used as the
    hash value instead of the net-snmp notation
    ALTEON-TS-PHYSICAL-MIB::agPortCurCfgPortName.

%MIBS
    A list of each mib needed.

        ('MIB-NAME' => 'itemToTestForPresence')

    The value for each entry should be a MIB object to check for to make
    sure that the MIB is present and has loaded correctly.

    $info->init() will throw an exception if a MIB does not load.

%MUNGE
    A map between method calls (from %FUNCS or %GLOBALS) and subroutine
    methods. The subroutine called will be passed the data as it gets it
    from SNMP and it should return that same data in a more human
    friendly format.

    Sample %MUNGE:

     (my_ip     => \&munge_ip,
      my_mac    => \&munge_mac,
      my_layers => \&munge_dec2bin
     )

Sample Subclass Let's make a sample Layer 2 Device subclass. This class will inherit the Cisco Vlan module as an example.

----------------------- snip --------------------------------

 # SNMP::Info::Layer2::Sample

 package SNMP::Info::Layer2::Sample;

 $VERSION = 0.1;

 use strict;
 use warnings;

 use Exporter;
 use SNMP::Info::Layer2;
 use SNMP::Info::CiscoVTP;

 @SNMP::Info::Layer2::Sample::ISA = qw/SNMP::Info::Layer2
                                       SNMP::Info::CiscoVTP Exporter/;
 @SNMP::Info::Layer2::Sample::EXPORT_OK = qw//;

 our ($VERSION, %FUNCS, %GLOBALS, %MIBS, %MUNGE, $AUTOLOAD, $INIT, $DEBUG);

 %MIBS    = (%SNMP::Info::Layer2::MIBS,
             %SNMP::Info::CiscoVTP::MIBS,
             'SUPER-DOOPER-MIB'  => 'supermibobject',
            );

 %GLOBALS = (%SNMP::Info::Layer2::GLOBALS,
             %SNMP::Info::CiscoVTP::GLOBALS,
             'name'              => 'supermib_supername',
             'favorite_color'    => 'supermib_fav_color_object',
             'favorite_movie'    => 'supermib_fav_movie_val',
             );

 %FUNCS   = (%SNMP::Info::Layer2::FUNCS,
             %SNMP::Info::CiscoVTP::FUNCS,
             # Super Dooper MIB - Super Hero Table
             'super_hero_index'  => 'SuperHeroIfIndex',
             'super_hero_name'   => 'SuperHeroIfName',
             'super_hero_powers' => 'SuperHeroIfPowers',
            );

 %MUNGE   = (%SNMP::Info::Layer2::MUNGE,
             %SNMP::Info::CiscoVTP::MUNGE,
             'super_hero_powers' => \&munge_powers,
            );

 # Override uptime() method from %SNMP::Info::GLOBALS
 sub uptime {
     my $sample = shift;

     my $name   = $sample->name();

     # this is silly but you get the idea
     return '600' if defined $name ;
 }

 # Create our own munge function
 sub munge_powers {
     my $power = shift;

     # Take the returned obscure value and return something useful.
     return 'Fire' if $power =~ /reallyhot/i;
     return 'Ice'  if $power =~ /reallycold/i;

     # Else
     return $power;
 }

 # Copious Documentation here!!!
 =head1 NAME
 =head1 AUTHOR
 =head1 SYNOPSIS
 =head1 DESCRIPTION
 =head2 Inherited Classes
 =head2 Required MIBs
 =head1 GLOBALS
 =head2 Overrides
 =head1 TABLE METHODS
 =head2 Overrides
 =cut

 1; # don't forget this line
----------------------- snip --------------------------------

SNMP::INFO INTERNALS Object Namespace Internal data is stored with bareword keys. For example $info->{debug}

SNMP Data is stored or marked cached with keys starting with an
underscore. For example $info->{_name} is the cache for $info->name().

Cached Table data is stored in $info->store() and marked cached per
above.

Package Globals These set the default value for an object upon creation.

$DEBUG
    Default 0. Sends copious debug info to stdout. This global sets the
    object's debug status in new() unless 'Debug' argument passed in
    new(). Change objects' debug status with $info->debug().

$BIGINT
    Default 0. Set to true to have 64 bit counters return Math::BigInt
    objects instead of scalar string values. See note under Interface
    Statistics about 64 bit values.

$NOSUCH
    Default 1. Set to false to disable RetryNoSuch option for
    SNMP::Session. Or see method in new() to do it on an object scope.

$REPEATERS
    Default 20. MaxRepeaters for BULKWALK operations. See "perldoc SNMP"
    for more info. Can change by passing "BulkRepeaters" option in new()

Data Munging Callback Subroutines munge_speed() Makes human friendly speed ratings using %SPEED_MAP.

     %SPEED_MAP = (
                    '56000'      => '56 kbps',
                    '64000'      => '64 kbps',
                    '115000'     => '115 kbps',
                    '1500000'    => '1.5 Mbps',
                    '1536000'    => 'T1',
                    '1544000'    => 'T1',
                    '2000000'    => '2.0 Mbps',
                    '2048000'    => '2.048 Mbps',
                    '3072000'    => 'Dual T1',
                    '3088000'    => 'Dual T1',
                    '4000000'    => '4.0 Mbps',
                    '10000000'   => '10 Mbps',
                    '11000000'   => '11 Mbps',
                    '16000000'   => '16 Mbps',
                    '16777216'   => '16 Mbps',
                    '20000000'   => '20 Mbps',
                    '44210000'   => 'T3',
                    '44736000'   => 'T3',
                    '45000000'   => '45 Mbps',
                    '45045000'   => 'DS3',
                    '46359642'   => 'DS3',
                    '51850000'   => 'OC-1',
                    '54000000'   => '54 Mbps',
                    '64000000'   => '64 Mbps',
                    '100000000'  => '100 Mbps',
                    '149760000'  => 'ATM on OC-3',
                    '155000000'  => 'OC-3',
                    '155519000'  => 'OC-3',
                    '155520000'  => 'OC-3',
                    '200000000'  => '200 Mbps',
                    '400000000'  => '400 Mbps',
                    '599040000'  => 'ATM on OC-12',
                    '622000000'  => 'OC-12',
                    '622080000'  => 'OC-12',
                    '1000000000' => '1.0 Gbps',
                    '2000000000' => '2.0 Gbps',
                    '2488000000' => 'OC-48',
                    '2500000000' => '2.5 Gbps',
                 )

    Note: high speed interfaces (usually 1 Gbps or faster) have their
    link speed in "ifHighSpeed". i_speed() automatically determines
    whether to use "ifSpeed" or "ifHighSpeed"; if the latter is used,
    the value is munged by munge_highspeed(). SNMP::Info can return
    speeds up to terabit levels this way.

munge_highspeed()
    Makes human friendly speed ratings for "ifHighSpeed".

munge_ip()
    Takes a binary IP and makes it dotted ASCII.

munge_inetaddress()
    Takes a binary IP address as defined by the SNMP InetAddress type
    and returns it as human readable string.

munge_mac()
    Takes an octet stream (HEX-STRING) and returns a colon separated
    ASCII hex string.

munge_prio_mac()
    Takes an 8-byte octet stream (HEX-STRING) and returns a colon
    separated ASCII hex string.

munge_prio_port()
    Takes an 2-byte octet stream (HEX-STRING) and returns a colon
    separated ASCII hex string.

munge_octet2hex()
    Takes a binary octet stream and returns an ASCII hex string.

munge_dec2bin()
    Takes a binary char and returns its ASCII binary representation.

munge_bits()
    Takes a SNMP2 'BITS' field and returns the ASCII bit string.

munge_counter64()
    If $BIGINT is set to true, then a Math::BigInt object is returned.
    See Math::BigInt for details.

munge_i_up()
    Net-SNMP tends to load "RFC1213-MIB" first, and so ignores the
    updated enumeration for "ifOperStatus" in "IF-MIB". This munge
    handles the "newer" definitions for the enumeration in IF-MIB.

    TODO: Get the precedence of MIBs and overriding of MIB data in
    Net-SNMP figured out. Hierarchy/precedence of MIBS in SNMP::Info.

munge_port_list()
    Takes an octet string representing a set of ports and returns a
    reference to an array of binary values each array element
    representing a port.

    If the element has a value of '1', then that port is included in the
    set of ports; the port is not included if it has a value of '0'.

munge_null()
    Removes control characters from a string.

munge_e_type()
    Takes an OID and return the object name if the right MIB is loaded.

Internally Used Functions resolve_desthost() Takes the SNMP::Session "DestHost" argument and determines if it is an 'IPv4' or 'IPv6' host. 'IPv6' hosts are prefixed with the "udp6:" "transport-specifier" as required by the underlying "Net-SNMP" library. If unable to determine the type of address or resolve a DNS name, dies with "croak".

$info->init()
    Used internally. Loads all entries in %MIBS.

$info->args()
    Returns a reference to the argument hash supplied to SNMP::Session

$info->class()
    Returns the class name of the object.

$info->error_throw(error message)
    Stores the error message for use by $info->error()

    If $info->debug() is true, then the error message is carped too.

$info->funcs()
    Returns a reference to the %FUNCS hash.

$info->globals()
    Returns a reference to the %GLOBALS hash.

$info->mibs()
    Returns a reference to the %MIBS hash.

$info->munge()
    Returns a reference of the %MUNGE hash.

$info->nosuch()
    Returns NoSuch value set or not in new()

$info->session()
    Gets or Sets the SNMP::Session object.

$info->store(new_store)
    Returns or sets hash store for Table functions.

    Store is a hash reference in this format :

    $info->store = { attribute => { iid => value , iid2 => value2, ... }
    };

$info->_global()
    Used internally by AUTOLOAD to create dynamic methods from %GLOBALS
    or a single instance MIB Leaf node name from a loaded MIB.

    Example: $info->name() on the first call dispatches to AUTOLOAD()
    which calls $info->_global('name') creating the method name().

    These methods return data as a scalar.

$info->_set(attr,val,iid,type)
    Used internally by set_multi() to run an SNMP set command. When run
    clears attr cache.

    Attr can be passed as either a scalar or a reference to an array or
    array of arrays when used with set_multi().

    Example: $info->set_name('dog',3) uses autoload to resolve to
    $info->_set('name','dog',3);

$info->_make_setter(val,iid)
    Used internally by AUTOLOAD to create dynamic methods from either
    %GLOBALS, %FUNCS, or a valid mib leaf from a loaded MIB which runs
    an SNMP set command. When run clears the attribute cache.

    Example: $info->set_name('dog',3) dispatches to autoload to resolve
    to $info->_set('name','dog',3) and _make_setter creates the
    set_name() method.

$info->set_multi(arrayref)
    Used to run an SNMP set command on several new values in the one
    request. Returns the result of $info->_set(method).

    Pass either a reference to a 4 element array [<obj>, <iid>, <val>,
    <type>] or a reference to an array of 4 element arrays to specify
    multiple values.

        <obj> - One of the following forms:
            1) leaf identifier (e.g., C<'sysContact'>)
            2) An entry in either %FUNCS, %GLOBALS (e.g., 'contact')
        <iid> - The dotted-decimal, instance identifier. For scalar MIB objects
                 use '0'
        <val>  - The SNMP data value being set (e.g., 'netdisco')
        <type> - Optional as the MIB should be loaded.

    If one of the set assignments is invalid, then the request will be
    rejected without applying any of the new values - regardless of the
    order they appear in the list.

    Example: my $vlan_set = [
    ['qb_v_untagged',"$old_vlan_id","$old_untagged_portlist"],
    ['qb_v_egress',"$new_vlan_id","$new_egress_portlist"],
    ['qb_v_egress',"$old_vlan_id","$old_egress_portlist"],
    ['qb_v_untagged',"$new_vlan_id","$new_untagged_portlist"],
    ['qb_i_vlan',"$port","$new_vlan_id"], ];

        $info->set_multi($vlan_set);

$info->load_all()
    Debugging routine. This does not include any overridden method or
    method implemented by subroutine.

    Runs $info->load_METHOD() for each entry in $info->funcs();

    Returns $info->store() -- See store() entry.

    Note return value has changed since version 0.3

$info->all()
    Runs $info->load_all() once then returns $info->store();

    Use $info->load_all() to reload the data.

    Note return value has changed since version 0.3

$info->_load_attr()
    Used internally by AUTOLOAD to create dynamic methods from %FUNCS or
    a MIB Leaf node name contained within a table of a loaded MIB.

    Supports partial table fetches and single instance table fetches.
    See "Partial Table Fetches" in SNMP::Info.

    These methods return data as a reference to a hash.

$info->_show_attr()
    Used internally by AUTOLOAD to return data called by methods listed
    in %FUNCS.

$info->snmp_connect_ip(ip)
    Returns true or false based upon snmp connectivity to an IP.

modify_port_list(portlist,offset,replacement)
    Replaces the specified bit in a port_list array and returns the
    packed bitmask

$info->_cache(attr, data)
    Cache retrieved data so that if it's asked for again, we use the
    cache instead of going back to Net-SNMP. Data is cached inside the
    blessed hashref $self.

    Accepts the leaf and value (scalar, or hashref for a table). Does
    not return anything useful.

$info->_munge(attr, data)
    Raw data returned from Net-SNMP might not be formatted correctly or
    might have platform-specific bugs or mistakes. The MUNGE feature of
    SNMP::Info allows for fixups to take place.

    Accepts the leaf and value (scalar, or hashref for a table) and
    returns the raw or the munged data, as appropriate. That is, you do
    not need to know whether MUNGE is installed, and it's safe to call
    this method regardless.

_validate_autoload_method(method)
    Used internally by AUTOLOAD to validate that a dynamic method should
    be created. Returns the OID of the MIB leaf node the method will get
    or set.

    1. Returns unless method is listed in %FUNCS, %GLOBALS, or is MIB
    Leaf node name in a loaded MIB for given class.
    2. Translates the MIB Leaf node name to an OID.
    3. Checks to see if the method access type is allowed for the
    resolved OID. Write access for set_ methods, read access for others.

$info->can()
    Overrides UNIVERSAL::can() so that objects will correctly report
    their capabilities to include dynamic methods generated at run time
    via AUTOLOAD.

    Calls parent can() first to see if method exists, if not validates
    that a method should be created then dispatches to the appropriate
    internal method for creation.

    Returns undef if the method does not exist and can not be created.

AUTOLOAD Each entry in either %FUNCS, %GLOBALS, or MIB Leaf node names present in loaded MIBs are used by AUTOLOAD() to create dynamic methods.

1. Returns unless method is listed in %FUNCS, %GLOBALS, or is a MIB Leaf
node name in a loaded MIB for given class.
2. If the method exists in %GLOBALS or is a single instance MIB Leaf
node name from a loaded MIB, _global() generates the method.
3. If a set_ prefix is present _make_setter() generates the method.
4. If the method exists in %FUNCS or is a MIB Leaf node name contained
within a table from a loaded MIB, _load_attr() generates the method.
5. A load_ prefix forces reloading of data and does not use cached data.
6. A _raw suffix returns data ignoring any munge routines.

Override any dynamic method listed in %GLOBALS, %FUNCS, or MIB Leaf node
name a by creating a subroutine with the same name.

For example to override $info->name() create `` sub name {...}'' in your
subclass.

COPYRIGHT AND LICENSE Changes from SNMP::Info Version 0.7 and on are: Copyright (c) 2003-2010 Max Baker and SNMP::Info Developers All rights reserved.

Original Code is: Copyright (c) 2002-2003, Regents of the University of
California All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.
    * Neither the name of the University of California, Santa Cruz nor the
      names of its contributors may be used to endorse or promote products
      derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.