Monitoring DNS resolving a non-existing name can crash moni.pl

[torbsjos]

When a DNS monitor is configured for a device (a DNS server), and the name isn't found. Moni.pl halts
with message "

Code: [Select]

Can't call method "answer" on an undefined value at ./moni.pl line 254."
This means that all devices that should be monitored after the DNS-server aren't monitored.
And there is no obvious warning that this has happened.
It should be possible to test if the reply from Net::DNS resolver->search is undefined to make this more stable.

[rickli]

Thanks for this find. I'll try to reproduce and fix it...

[sjobergh]

Any update on this problem ?

[rickli]

This one fell through the cracks, sorry. It will alert if a name doesn't exist now. You can tweak your moni.pl in the TestTgt function by doing as torbsjos said:

            if( defined $query ){
               foreach my $rr ($query->answer)...

And add this after:
            }else{
               $latency = -1;
               misc::Prt("DNS :No answer for $mon{$tgt}{to}\n");
            }