OpenSSH 8.9p1-1 Connects successfully but then hangs - Killing ssh-agent resolves the issue

[Jim Garrison]

On 4/1/2022 2:21 AM, Henry S. Thompson wrote:
> Jim Garrison via Cygwin writes:
> 
>> My Cygwin ssh client stopped working... It would successfully connect to
>> the remote (Debian) host but then hang without displaying the command
>> prompt.  See debug output attached, as well as cygcheck output.
>>
>> I decided to run setup to see if there was a newer version of openssh.
>> In preparation for that I always terminate all Cygwin processes because
>> they will interfere with the update.  I killed the ssh-agent process and
>> on a whim decided to try connecting again.  This time it worked.
>>
>> This would seem to indicate something in ssh-agent is interfering with
>> the connection.  There are no credentials loaded into ssh-agent.
> 
> There are reports out there of ssh-agent getting stuck: just out of
> curiousity if this happens again, check to see if ssh-agent is using
> 100% of a CPU.  If so then search for "ssh-agent" "100% CPU" to see
> what the likely culprits are.
> 
> ht

Thanks for confirming that this is a possible issue.  I didn't notice if
ssh-agent was in a CPU loop, but will take note if/when it happens
again.

-- 
Jim Garrison
jhg@acm.org