3560 losing connection, but no link down

[meneerB]

hi,
Nagios loses connection so now and then to the C3560-IPBASE-M), Version 12.2(25)SEB4.
5 to 20 times a day I cannot get a reply and can also not connect to the switch.

the switch is connected to our backbone switch with a 1gb cupper link.
The users don't notice this and i don't see link down messages on our backbone swicth log.

what can I do?

 

[burtsbees]

What is "Nagios"??? The backbone switch? How do you know it actually loses connection, rather than, say, the cpu spikes at 100% for a few minutes 5-20 times a day? This will also prevent you from connecting, maybe due to IP traffic, interrupts, etc...

I would do a sh proc cpu in the 3560...

/

tim@tim-laptop ~ $ sudo apt-get install windows
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Couldn't find package windows...Thank Goodness!

 

[meneerB]

using Linux and not knowing Nagios..
it's a monitoring tool, in this case a ping every 5 min.
you can be right that the switch is to much occupied with something else and therefore not replying to pings.
i dont think so, but it could be.
can i check this with traps to a syslog server, e.g. > 50%?

 

[vipergg]

Do a show proc cpu history and see if you are getting extremely cpu spikes when this happens , it keeps up to like 72 hours .

 

[ISPKing]

Lol I think burts was j/k with you,

Anyway check out intermapper, they have a 5 free device liscence and one of there snmp probes is a cisco CPU and mem
poller, set it up and it will give u live statistics for any interval you choose, plus historical. (nagios is kind of a pain in the ass for this IMO)

I apologize for the crappy writing, on an iPhone.
No more excuses when I get my ipad tho >

 

[meneerB]

just 30%.

thank you both for your input.

I'll just wait 2 / 3 days and post again.

 

[meneerB]

so... no cpu problem afterall.

the switch had an ip within the same vlan as the userports.
to avoid any conflicts, i created a 2nd vlan, a mgt vlan, which we also use for our other switches.

i changed the native vlan of the switch the our mgtvlan, changed the ip address and since 3 days i don't receive any timeouts anymore.

thx all for the help, that should have done the trick....