SSH 3.2.0: Too many open connections --- how to check what's open?
I am managing a compute server under Tru64 Unix V5.1B-3. Access is
allowed via ssh only. Access is managed by the sshd2 supplied with the
OS, i.e. "SSH Secure Shell Tru64 UNIX 3.2.0".
The maximum number of connections is set to 50.
Recently, connections have been refused on several occasions with the
error message "Received disconnect from 18.104.22.168: 12: Too many
connections.", while the auth.log file on my machine shows " Too many
open connections (max 50, now open 50)".
But netstat showed at that time only seven open connections. Five of
those connections forwarded X11, but even if I count those as
connections, I only get to 13.
Is there any way to query the sshd for the open connections? If not,
what debug level do I need to choose when I restart sshd to get
sufficient information to trace "zombie" connections?
And would it be safe to simply restart sshd2 to get rid of "zombie"
connections, or could such a restart open the door for intruders?
Thanks in advance for any information!