a Catalyst 4948 has CPU usage rising above our Alarm treshold (60%).
It does no harm to the production but I was curious and investigated the phenomenon.
I followed the troubleshooting path presented in this document https://www.cisco.com/c/en/us/support/docs/switches/catalyst-4000-series-switches/65591-cat4500-high-cpu.html.
I started to monitor the traffic send to the CPU and found several telnet session between a machine and several Cisco 25xx Terminal Servers.
I am surprised to see that kind of traffic forwarded at the CPU level. Does anybody has an explaination for that ?
Hi @hekho ,
Check this link:
It has some information that could guide you with your doubt.
thanks for your recommendation. I have to say the Catalyst itself is not involved in the telnet sessions.
The CPU rise seems to be correlated by Layer-2 forwarding as showned by K2CpuMan Review at the of CPU usage.
Thank you very much.
Ha ha. At the moment that's not an option otherwise I would have done it already :-D
And as I wrote, there's no impact on the production. The goal here is to understand why on earth telnet traffic and also LDAP make their way to the the CPU. That does not make sense to me.
Thanks for your comment. The telnet traffic I am talking about involves servers on the network not the switch itself. As far as I know, that should belong to data plane.