DHCP service update

[imincik]

Use cases

• No DHCP server in network: GIS.lab DHCP: yes, LAN: static IP, WAN: static IP, connection forwarding: yes
• DHCP present in network: GIS.lab DHCP: no, LAN: via DHCP, WAN: no, connection forwarding: no
• Vagrant: GIS.lab DHCP: yes, LAN: static IP, WAN: static IP, connection forwarding: yes, Note: laptop connected via WiFi, but GIS.lab nework binded to eth0

Tasks

DHCP service configuration

• DHCP service must be always turned off by default
• DHCP service will be configured to work in range 192.168.5.0/255 by default

Default network configuration (server)

Changed network configuration in /etc/network/interfaces

• one IP address with DHCP client
• other use case with two static IP addresses commented out

Removal of DNS service

• DNS service should be removed from server and substituted by single "server.gis.lab" record dynamically written to /etc/hosts file on client machines

Config cleanup

Following configuration variables should be removed:

• GISLAB_NETWORK
• GISLAB_SERVER_INTEGRATION
• GISLAB_INTEGRATION_FALLBACK

Other tasks

• update all documentation about networking and client boot process
• remove all no longer needed patches around udhcpc on client machines

[landam]

FYI: I have created for development issues a new branch dhcp-service-dev

[landam]

See 3507cb2c7d541b4c5989649013f55f13c0e16a5f

[landam]

I tested two cases bellow:

• DHCP present in network: GIS.lab DHCP: no, LAN: via DHCP, WAN: no, connection forwarding: no

On third-party DHCP server NEXT_SERVER and FILE options were defined. File /var/lib/tftpboot/gislab/pxelinux.cfg/default has been manually changed to reflect Unit IP address. Clients booted and system seems to work.

• Vagrant: GIS.lab DHCP: yes, LAN: static IP, WAN: static IP, connection forwarding: yes, Note: laptop connected via WiFi, but GIS.lab nework binded to eth0

Vagrant machine created. Then required services have been started:

sudo service isc-dhcp-server start
sudo service bind9 start
sudo service gislab-connection-forwarding start

Clients booted via PXE. HTTP boot hasn't been tested yet.

[mpastor]

It's no more necessary to modify /var/lib/tftpboot/gislab/pxelinux.cfg/default configuration file - client will use IP server address from DHCP options acquired from DHCP server.