[c-nsp] Unable to clear vty session on 3750

[Nick Hilliard]

On 31/07/2012 10:29, Bouazza Djamel wrote:
> I have an issue today with nombers of vty sessions.We have no console
> access for this device.See below please :

three options here:

1.  configure a timer on the vty and use TCP keepalives to stop this from
happening in future:

switch#conf t
switch(config)#service tcp-keepalives-in
switch(config)#service tcp-keepalives-out
switch(config)#line vty 0 15
switch(config)# exec-timeout 5

If this fails to clear things after 30 minutes, then try:

2.  clear the TCB (transmission control block - an internal TCP data
structure) for each vty line.

You can get the TCB id for each line using:

switch#show tcp brief

It's in the first column.  Confirm it first with:

switch#show tcp tcb <tcbid>

You can clear the TCB using:

switch#clear tcp tcb <tcbid>

If this fails:

3. reboot.

Probably #2 will work this time and #1 will prevent the problem from
recurring in future.

Nick