ssh hangs instead of exiting

[Ed Phillips]

On Mon, 8 Oct 2001, James Oden wrote:

> Date: Mon, 8 Oct 2001 14:52:20 -0400 (EDT)
> From: James Oden <joden at eworld.wox.org>
> To: openssh-unix-dev at mindrot.org
> Subject: Hanging ssh session...
>
> Hi All,
>
> I am not sure if this is the same thing as the hang on exit bug, so sorry if
> this is a duplication of previous stuff.
>
> Essetntially I am experiencing ssh hangs with about .5% - 1% of my
> connections.  I am running 2.9p2, on Solaris 7.  I actually have empirical
> data on the hangings, as I wrote a script to create these connections
> in an endless loop, setting an alarm so I could recover from a hang.
> I will place this script at the end of my email.

By the way, in my case, the hang of the orginal ssh process and error
messages occurs more often than not... but strangely enough, not _every_
time.  It must be some kind of race.  The process I use is - do "ssh -n
<host> xterm", and then when the xterm pops up, immediately press CTRL-d
so that the xterm exits.  Here's what I see on the client side for several
runs:

polycut:~> ssh -n mahler xterm
channel_lookup: 0: bad id: channel free
client_input_channel_req: channel 0: unknown channel
^CKilled by signal 2.
polycut:~> ssh -n mahler xterm
channel_lookup: 0: bad id: channel free
client_input_channel_req: channel 0: unknown channel
^CKilled by signal 2.
polycut:~> ssh -n mahler xterm
polycut:~> ssh -n mahler xterm
polycut:~> ssh -n mahler xterm
channel_lookup: 0: bad id: channel free
client_input_channel_req: channel 0: unknown channel
^CKilled by signal 2.
polycut:~> ssh -n mahler xterm
channel_lookup: 0: bad id: channel free
client_input_channel_req: channel 0: unknown channel
^CKilled by signal 2.
polycut:~> ssh -n mahler xterm
channel_lookup: 0: bad id: channel free
client_input_channel_req: channel 0: unknown channel
^CKilled by signal 2.
polycut:~> ssh -n mahler xterm
channel_lookup: 0: bad id: channel free
client_input_channel_req: channel 0: unknown channel
^CKilled by signal 2.
polycut:~> ssh -n mahler xterm
channel_lookup: 0: bad id: channel free
client_input_channel_req: channel 0: unknown channel
^CKilled by signal 2.
polycut:~> ssh -n mahler xterm
channel_lookup: 0: bad id: channel free
client_input_channel_req: channel 0: unknown channel
^CKilled by signal 2.
polycut:~> ssh -n mahler xterm
polycut:~>

Someone has suggested that I try 2.9.9p2 (are there fixes in 2.9.9p2
related to this problem?) and I'll try that ASAP.

Side question:  Can anyone tell me how to build openssh so that it has
"built-in" entropy collection instead of needing to build/install/run
PRNGd?

Thanks,

	Ed

Ed Phillips <ed at udel.edu> University of Delaware (302) 831-6082
Systems Programmer III, Network and Systems Services
finger -l ed at polycut.nss.udel.edu for PGP public key