Line Protocol keeps fluctuating

[justyouraverageguy88]

Hello guys, I'm fairly new to Networking and Cisco, we were asked to create 3 networks that are connected to an ISP Router, at first it works fine but once I've used Rip V2 and HSRP, all of the line protocols of the interfaces of the routers keep alternating between up and down and can't interact with them anymore. Keep someone tell me where I went wrong so I can improve and prevent it from happening again? Thanks for your feedback.

[Georg Pauwen]

Hello,

it looks like your serial interfaces are partially on different subnets. Due to the complexity of your network, it is very difficult to figure out which serial interface is connected to what.

Put a description on each serial interface, as in this example:

interface Serial0/0/0

description Link to Serial0/0/0 RouterX Subnet 40.0.0.0/30

Also, the clock rate needs to be configured on only one side of the serial link. It is configured on both ends. Make sure to remove that from one end of each serial link.

[Georg Pauwen]

Hello,

something is wrong with the serial links...I am trying to figure out what.

[justyouraverageguy88]

Hey, 

I think the problem is in the HSRP aspect. I removed it and it seemed to be working somewhat I'll try to reconfigure it again 

[Georg Pauwen · Accepted solution]

Hello,

I have done some extensive testing, and I am pretty sure that Packet Tracer itself is the problem. When you shut all serial links and leave just one up, there is no problem with that link. As soon as you enable the others, the links start to flap. So it looks like the 2911 routers cannot handle the amount of links. 

I don't know if e.g. the 4331 with NIM-2T modules work any better. Has that topology been given to you, or have you designed that yourself, that is, did you, or somebody else, chose the routers ?

[justyouraverageguy88]

I designed the topology myself running on the latest Packet Tracer version. Perhaps the latest version is buggy? A friend of mine also stated that he just restarted the application and it seemed to be working fine so yeah might be the Packet Tracer.

[Georg Pauwen]

Hello,

I am using the latest version of Packet Tracer (8.1.1) on a computer with 32G of memory, the file crashes after about 5 minutes. I think it is definitely a Packet Tracer issue (related to the amount of serial links, which require clocking, that is I think where the problem is...)