Cisco 1720 problem

[kkiedrowski]

Currently we use a Cisco 1720 to connect to the internet. now the router is plugged directly into our switches. The problem is that recently we experience internet slowdowns so bad that I cannot even telnet into the router. I need to power it off and on and then do a reload so everything works fine.
I was wondering if anyone ahs run across this or is there something I should be doing differently.
thanks again and happy new year

 

[dx1]

If it happens again, console into it to see if there's any errors. It sounds like the nachi/blaster worm. Check this link for more info:

http://www.cisco.com/warp/public/707/advisory.html

 

[kkiedrowski]

I forgot to mention that I am a novie at best when it comes to working on the router. Unfortunately that makes me the most knowledgable here.
I start the debug on the fastethernet and ethernet-interface
If I view the diag log it shows me this:

Syslog logging: enabled (0 messages dropped, 0 flushes, 0 overruns)
Console logging: level debugging, 212 messages logged
Monitor logging: level debugging, 0 messages logged
Buffer logging: disabled
Trap logging: level informational, 12 message lines logged

I am not sure how to digest this information.
thanks

 

[lgarner]

You'll want a bit of buffer logging, especially if you don't have a log host.

Router# config term
Router(config)# service timestamps log datetime localtime timezone
Router(config)# logging buffered 4096 (or alarger size).

Anyway, I had the same issue. Since you're using an Ethernet WIC I have to ask: What IOS version are you using? The email from Cisco that I received last week said:

"You are currently running 12.2(4)T, and the minimum IOS that supports this card in a 1721 is 12.2(8)T. The following IOS's support the WIC-1ENET card in a 1721 router:

12.2(4)YA, 12.2(4)YB, 12.2(4)YH, 12.2(8)T, 12.2(8)YJ, 12.2(8)YL, 12.2(8)YM, 12.2(8)YN, 12.2(11)T, 12.2(11)YU, 12.2(11)YV, 12.2(13)T, 12.3(1). "

I upgraded to 12.3(1) and haven't seen the problem, but it also went away when I switched to the secondary (identically configured) router. Too soon to tell, but the IOS version might be worth a look.

 

[kkiedrowski]

Version 12.0(3)T3 is my current version so maybe the upgrade will help

 

[kkiedrowski]

well i have gone from 12.0(3)T3 to 12.0(7)T3
since i do not have a IOS upgrade license I bet that means that is far as i can go.

 

[MWM]

kkiedrowski

Along with the router IOS tack, you may be able to learn a lot from your switches, especially if they are Cisco devices. These provide a wealth of info.

To isolate the problem, though, at the hardware level, can you remove inside LAN segments? Is the (problem) traffic coming from an inside segment?

Without software tools it is almost a matter of luck finding the problem source.

If your boss is level-headed he may see the wisdom in sending you to some classes and providing you with some network diagnostic tools.

I would beware of a boss that wants to lay it all on you and yet not give you the tools to do the work. You have only two hands and a person can only do so much without help.

Yours,
Mike