Routers Cannot Communicate after Enabling RIPv2

xyzzklk commented 3 days ago

Describe the bug First I configured RIPv2 on three Cisco IOSv15.9(3)M6 routers that are connected to each other. After some time, they cannot receive each other's RIP update request. They also cannot ping each other, and I can't even start a packet capture to see what's going on.

Because I can't even start a packet capture, I suspect this is a problem of GNS3.

GNS3 version and operating system:

OS: Windows 10
GNS3 version 2.2.49
GNS3 Hyper-V VM

To Reproduce Steps to reproduce the behavior:

Connect and configure the router interfaces as shown in the following image:
Use the following command to enable RIPv2 on R1, R2 and R3
```
router rip
version 2
no auto-summary
```
and use the network command to add the interfaces that should have RIP activated on.

Here are the interface and RIP statuses of R1,2&3. R1


R1#sh ip int br
Interface                  IP-Address      OK? Method Status                Protocol
GigabitEthernet0/0         192.168.1.1     YES manual up                    up
GigabitEthernet0/1         unassigned      YES unset  administratively down down
GigabitEthernet0/2         unassigned      YES unset  administratively down down
GigabitEthernet0/3         unassigned      YES unset  administratively down down
R1#sh ip protocol
*** IP Routing is NSF aware ***

Routing Protocol is "application" Sending updates every 0 seconds Invalid after 0 seconds, hold down 0, flushed after 0 Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Maximum path: 32 Routing for Networks: Routing Information Sources: Gateway Distance Last Update Distance: (default is 4)

Routing Protocol is "rip" Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Sending updates every 30 seconds, next due in 17 seconds Invalid after 180 seconds, hold down 180, flushed after 240 Redistributing: rip Default version control: send version 2, receive version 2 Interface Send Recv Triggered RIP Key-chain GigabitEthernet0/0 2 2 No none Interface Send Recv Triggered RIP Key-chain Automatic network summarization is not in effect Maximum path: 4 Routing for Networks: 192.168.1.0 Routing Information Sources: Gateway Distance Last Update 192.168.1.2 120 02:37:39 Distance: (default is 120) R1#

R2

R2#sh ip int br Interface IP-Address OK? Method Status Protocol GigabitEthernet0/0 192.168.2.1 YES manual up up GigabitEthernet0/1 192.168.1.2 YES manual up up GigabitEthernet0/2 unassigned YES unset administratively down down GigabitEthernet0/3 unassigned YES unset administratively down down R2#sh ip protocol IP Routing is NSF aware

Routing Protocol is "application" Sending updates every 0 seconds Invalid after 0 seconds, hold down 0, flushed after 0 Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Maximum path: 32 Routing for Networks: Routing Information Sources: Gateway Distance Last Update Distance: (default is 4)

Routing Protocol is "rip" Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Sending updates every 30 seconds, next due in 9 seconds Invalid after 180 seconds, hold down 180, flushed after 240 Redistributing: rip Default version control: send version 2, receive version 2 Interface Send Recv Triggered RIP Key-chain GigabitEthernet0/0 2 2 No none Interface Send Recv Triggered RIP Key-chain GigabitEthernet0/1 2 2 No none Automatic network summarization is not in effect Maximum path: 4 Routing for Networks: 192.168.1.0 192.168.2.0 Routing Information Sources: Gateway Distance Last Update Distance: (default is 120)

R2#

R3 (With output from `debug rip ip`)

R3#show ip int br Interface IP-Address OK? Method Status Protocol GigabitEthernet0/0 unassigned YES unset administratively down down GigabitEthernet0/1 192.168.2.2 YES manual up up GigabitEthernet0/2 unassigned YES unset administratively down down GigabitEthernet0/3 unassigned YES unset administratively down down R3#show ip proto IP Routing is NSF aware

Routing Protocol is "application" Sending updates every 0 seconds Invalid after 0 seconds, hold down 0, flushed after 0 Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Maximum path: 32 Routing for Networks: Routing Information Sources: Gateway Distance Last Update Distance: (default is 4)

Routing Protocol is "rip" Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Sending updates every 30 seconds, next due in 2 seconds Invalid after 180 seconds, hold down 180, flushed after 240 Redistributing: rip Default version control: send version 2, receive version 2 Interface Send Recv Triggered RIP Key-chain GigabitEthernet0/1 2 2 No none Interface Send Recv Triggered RIP Key-chain Automatic network summarization is not in effect Maximum path: 4 Routing for Networks: 192.168.2.0 Routing Information Sources: Gateway Distance Last Update 192.168.2.1 120 02:40:33 Distance: (default is 120)

R3# Oct 4 01:48:10.636: RIP: sending v2 update to 224.0.0.9 via GigabitEthernet0/1 (192.168.2.2) Oct 4 01:48:10.637: RIP: build update entries - suppressing null update

4. Then everything goes well. They communicate and correctly exchange routing information.
5. But after some time, the RIP routes are removed from their routing table. The Last Update time on each router shows a long time ago (as shown in the RIP status output).
6. When I try to make them ping each other, they won't do.

R3#ping 192.168.2.1 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.2.1, timeout is 2 seconds: ..... Success rate is 0 percent (0/5) R3#

7. They still say they're sending RIP updates, as shown in the output of `show ip protocol` and `debug ip rip`.
8. When I start a packet capture, or even add a note on the topology, GNS3 will give me a `404 not found` error. Wireshark will be shown as blank.
![image](https://github.com/user-attachments/assets/4d53e29d-8f99-43bd-9e67-7b0e79e5ffad)

**Running-config of all three routers**
```bash
R1#sh run
Building configuration...

Current configuration : 3220 bytes
!
! Last configuration change at 22:01:39 UTC Thu Oct 3 2024
!
version 15.9
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
!
no aaa new-model
!
!
!
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
!
!
!
!
!
no ip icmp rate-limit unreachable
!
!
!
!
!
!
no ip domain lookup
ip cef
no ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
redundancy
!
no cdp log mismatch duplex
!
ip tcp synwait-time 5
!
!
!
!
!
!
!
!
!
!
!
!
!
interface GigabitEthernet0/0
 ip address 192.168.1.1 255.255.255.0
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/2
 no ip address
 shutdown
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/3
 no ip address
 shutdown
 duplex auto
 speed auto
 media-type rj45
!
router rip
 version 2
 network 192.168.1.0
 no auto-summary
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
ipv6 ioam timestamp
!
!
!
control-plane
!
banner exec ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
banner incoming ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
banner login ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
!
line con 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line aux 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line vty 0 4
 login
 transport input none
!
no scheduler allocate
!
end

R1#

(Somehow I accidentally restarted R2 and forgot to save the running config, but I configured it again, so things might be a little bit different than what was originally)

R2#show running-config
Building configuration...

Current configuration : 3254 bytes
!
! Last configuration change at 02:08:55 UTC Fri Oct 4 2024
!
version 15.9
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R2
!
boot-start-marker
boot-end-marker
!
!
!
no aaa new-model
!
!
!
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
!
!
!
!
!
no ip icmp rate-limit unreachable
!
!
!
!
!
!
no ip domain lookup
ip cef
no ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
redundancy
!
no cdp log mismatch duplex
!
ip tcp synwait-time 5
!
!
!
!
!
!
!
!
!
!
!
!
!
interface GigabitEthernet0/0
 ip address 192.168.2.1 255.255.255.0
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/1
 ip address 192.168.1.2 255.255.255.0
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/2
 no ip address
 shutdown
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/3
 no ip address
 shutdown
 duplex auto
 speed auto
 media-type rj45
!
router rip
 version 2
 network 192.168.1.0
 network 192.168.2.0
 no auto-summary
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
ipv6 ioam timestamp
!
!
!
control-plane
!
banner exec ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
banner incoming ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
banner login ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
!
line con 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line aux 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line vty 0 4
 login
 transport input none
!
no scheduler allocate
!
end

R2#

R3#sh run
Building configuration...

Current configuration : 3220 bytes
!
! Last configuration change at 01:15:27 UTC Fri Oct 4 2024
!
version 15.9
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R3
!
boot-start-marker
boot-end-marker
!
!
!
no aaa new-model
!
!
!
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
!
!
!
!
!
no ip icmp rate-limit unreachable
!
!
!
!
!
!
no ip domain lookup
ip cef
no ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
redundancy
!
no cdp log mismatch duplex
!
ip tcp synwait-time 5
!
!
!
!
!
!
!
!
!
!
!
!
!
interface GigabitEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/1
 ip address 192.168.2.2 255.255.255.0
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/2
 no ip address
 shutdown
 duplex auto
 speed auto
 media-type rj45
!
interface GigabitEthernet0/3
 no ip address
 shutdown
 duplex auto
 speed auto
 media-type rj45
!
router rip
 version 2
 network 192.168.2.0
 no auto-summary
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
ipv6 ioam timestamp
!
!
!
control-plane
!
banner exec ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
banner incoming ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
banner login ^C
**************************************************************************
* IOSv is strictly limited to use for evaluation, demonstration and IOS  *
* education. IOSv is provided as-is and is not supported by Cisco's      *
* Technical Advisory Center. Any use or disclosure, in whole or in part, *
* of the IOSv Software or Documentation to any third party for any       *
* purposes is expressly prohibited except as otherwise authorized by     *
* Cisco in writing.                                                      *
**************************************************************************^C
!
line con 0
 --More--
*Oct  4 02:01:34.032: RIP: sending v2 update to 224.0.0.9 via GigabitEthernet0/1 (192.168.2.2)
*Oct  4 02:01:34.033: RIP: build update entries - suppressing null update
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line aux 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line vty 0 4
 login
 transport input none
!
no scheduler allocate
!
end

R3#

smart2128 commented 3 days ago

Router configurations are correct. I copied and pasted yours and it works as expected, but I'm on a local GNS3 server on Linux.

xyzzklk commented 2 days ago

Router configurations are correct. I copied and pasted yours and it works as expected, but I'm on a local GNS3 server on Linux.

Interesting. Mine works as well right after configuration, but after about 5 minutes, their communication starts to corrupt.

The reason I discovered this was that I left my computer running for some time and then went back to check. By the way, it was running, not sleeping or locked.

smart2128 commented 2 days ago

No problems also after a few hours or resuming from suspension. Maybe you can try if something changes running the GNS3 VM on a different hypervisor or using a remote Linux server.

GNS3 / gns3-gui

Routers Cannot Communicate after Enabling RIPv2 #3640