I currently am running a script that, among other things, runs ssh commands on remote systems and processes the output. This script had been running fine as of July 8, but recently it appears to have just frozen. Looking at the log that the script prints to, it seems to have stopped at August 9 at ~4:15 AM while trying to scan a system via SSH. Running ps, I see the following: 

root     15347 15339 15261  0.0  1.2  57984 48320 ?        S    Jul08 
+  4:37   /usr/bin/perl /srv/www/cgi-bin//sysManager.pl /srv/www/cgi-b
+in/
root     18773 18773 18773  0.0  0.2  12352  8576 pts/0    Ss+  Aug09 
+  0:00     ssh -xMN -o NumberOfPasswordPrompts=1 -o PreferredAuthenti
+cations=keyboard-interactive,password -S /root/.libnet-openssh-perl/h
+scroot-[hostnameRemoved]-15347-95046 -o User=[usernameRemoved] -- [ho
+stnameRemoved]
root     18775 15339 15261  0.0  0.2  12096  8064 ?        S    Aug09 
+  0:00     ssh -S /root/.libnet-openssh-perl/[usernameRemoved]-[hostn
+ameRemoved]-15347-95046 -o User=[usernameRemoved] -- [hostnameRemoved
+] [cmdRemoved]

[download]

The lines of code that equate to this scan are: 

my $ssh = Net::OpenSSH->new($host, (user => $username, password => $pa
+ssword, timeout=>30));
my($stdout, $stderr) = $ssh->capture2({timeout => 30}, $cmd);

[download]

Is there any way to debug what may have happened here and why it didn't time out, in the hopes that I can avoid this in the future or submit a bug report? I see it says in the Net::OpenSSH documentation regarding the "timeout" parameter that "As the Secure Shell protocol does not support signalling remote processes, in order to abort the remote process its input and output channels are closed. Unfortunately this aproach does not work in some cases." Is there another way to force this timeout? I've tried running the script again and didn't hit the problem this time, but am guessing it will happen again randomly later and don't want to have to manually restart the script every time it does.

In reply to Net::OpenSSH cmd not timing out as requested by Only1KW

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