after some time SSH won't work

[evgenie.daniel1]

hello 

i have cisco 860 router. after some days or a week i cannot use SSH anymore unless i make reboot. why is that?

[Leo Laohoo]

With that kind of behaviour, it sounds like an IOS bug.
Have you tried to upgrade the IOS of the router?

[evgenie.daniel1]

nope never

how to upgrade ?

[Leo Laohoo]

Copy the IOS into the router, change the boot variable string and then reboot.

[Georg Pauwen]

Hello,

on a side note, what does your SSH configuration look like ? Are you using version 2 ? Sample config would be something like this:

ip ssh version 2
ip ssh time-out 60
ip ssh authentication-retries 3
crypto key generate rsa (1024 or higher recommended)

[Julio E. Moisa]

Hi

Have you tried removing the following lines:

no ip ssh port 2222 rotary 1

no ip ssh source-interface GigabitEthernet0

line vty 0 4
no rotary 1

[evgenie.daniel1]

what does it means "rotary 1"  ?

[rasmus.elmholt]

Try a show line to see if you have some old SSH connections hanging on.
I see this a lot when i configure exce-timout 0 on my line vty 0 15.
If my SSH connections is cut it will still be active on the router and when the max of 16 is reached you cannot ssh/telnet to the device anymore.

[evgenie.daniel1]

i don't have line 0 15 configured

i have only line 0 4  and it is configured with exec timeout   30

[rasmus.elmholt]

Hi
Is it because your device only support 0 4 lines?
3 of the 5 lines are currently used(the * in front of the vty line) you can manually clear the lines with clear line vty 0.
Could you do a show run all | sec line vty?
It looks like something is logging in to your device and the sessions hangs. If you want to know the ip address configure anaccess-list using access-class one the line with the log keyword.