ASR9K access with ssh does not work.

[udlcruz]

Hi all, I have a ASR9001 enabled SSH server, it was working fine but when I try to access these messages appear:

P/0/RSP0/CPU0:Apr 21 05:31:41 : SSHD_[65747]: %SECURITY-SSHD-3-ERR_GENERAL : Failed to allocate pty

RP/0/RSP0/CPU0:Apr 21 05:31:43 : devc-vty[181]: %MGBL-TTY-3-KERNEL : Unexpected internal error encountered 'Resource temporarily unavailable'  : pkg/bin/devc-vty : (PID=557258) :  -Traceback= 4bc37e70 4de37b0c 4de3c3d4 4bc3a2d0 4bc3df28 4bc3540c 4bc3cd00 4ba74650 4ba7514c 4ba702c8 4bc5754c 4bc58464 40000130 40000d18

RP/0/RSP0/CPU0:Apr 21 05:31:43 : devc-vty[181]: %MGBL-VTY-3-SESSION : Error performing TTY session operation 'Checking access parameters for VTY': a194060d, ''tty-server' detected the 'fatal' condition 'TTY SERVER INTERNAL: Unknown error condition': Permission denied'

In the cisco page gives no recommendation for this, any comments for this?

regards

[Richard Burts]

While I can not explain the details of the messages, it is very clear that there is some type of error (probably a software issue more likely than a hardware issue). This relates to the part that says "Unexpected internal error" and to the presence of traceback information. In my experience traceback is always related to a software issue.

Is this perhaps a transient (temporary) problem and after a while SSH worked again? Or is the problem continuing?

As a workaround it might help to reload the router. That might restore normal function for SSH. I believe that a longer term solution will involve upgrading to different code. If the router is covered by a maintenance contract it would be good to open a TAC case on this and get a more authoritative explanation than I am able to give.

HTH

Rick

[rahul.vijairania · Accepted solution]

Give a restart to the VTY service.

process restart devc-vty location 0/RSP0/CPU0

Hope this will solve your problem as i was facing the same problem with my asr9000.

Resolved after resart of vty service

[udlcruz]

Hi Rahul,

Yes, that was the solution, you check with the command (show process blocked) if you find (devc-vty) for various time, they can be ssh or telnet sessiones who remained hung.
So you apply the (process restart devc-vty) command to unlock the process.

With this the problem is solved.

Thank you.