FWIW, I see this as well. A /etc/init.d/ssh restart does clear everything out and ssh is ok for a while. I noticed that nagios tends to aggravate things (/usr/lib/nagios/plugins/check_ssh -4 <ip address>), but not immediately after a restart. Eg, I had 883 zombies a moment ago, then I did restart (which cleared them all out), and now I can't trigger it immediately. :(
FWIW, I see this as well. A /etc/init.d/ssh restart does clear everything out and ssh is ok for a while. I noticed that nagios tends to aggravate things (/usr/lib/ nagios/ plugins/ check_ssh -4 <ip address>), but not immediately after a restart. Eg, I had 883 zombies a moment ago, then I did restart (which cleared them all out), and now I can't trigger it immediately. :(