I saw a similar post about high CPU on a 2960. They said the CPU is high until they telnet then it drops back to normal, well our issue is opposite.
When we telnet, Console works fine, to the switch the CPU goes right up to 100% and it stays that way even when we log out of the telnet session. What I have to do is do a show tcp brief and find the tcb number for the telnet session and run the clear tcp tcb tcb number and then the CPU goes back to normal. Has anyone seen of heard of this issue? This just happened out of the blue, no major config changes. Someone was telneted in the switch not making changes and all was good and they logged out and not too long after someone else logged in and we were alerted that the CPU was 100%, and it has been acting that way ever since.
They are two 6509's VSS running image is
Now I know we should update and maybe this would go away but this is our main switch and down time would be very difficult for what maybe considered just an annoyance and not impacting users. Just looking to see if anyone else has seen or heard of this and see if it is fixable without downtime. We are going to try and get some downtime to update the image but that won't be for a few months or so.