Fix for MRTG Generating SNMP_Session Error in Debian Wheezy (and possibly Ubuntu)

This article is published at Linux Tools of the Trade.

Lately, after an upgrade from Debian Squeeze to Debian Wheezy, MRTG is sending emails every few minutes when it runs from the crontab. This is quickly filling up my Inbox. There error message is as follows:

Subroutine SNMP_Session::pack_sockaddr_in6 redefined at /usr/share/perl/5.14/ line 67.
 at /usr/share/perl5/ line 149

After waiting for a while to see if a fix came from Debian, I decided to look around on my own. It seems there is a patch that works, but it has not been propagated out to the repositories. Luckily, this error problem is easy to fix.

You can apply the patch at the link above, or you can just edit a file and make 2 quick changes: Edit the file


Change line #149:

old: import Socket6;
new: Socket6->import(qw(inet_pton getaddrinfo));

Then change line #609:

old: import Socket6;
new: Socket6->import(qw(inet_pton getaddrinfo));

That seems to fix the problem quite well. Hopefully the Debian maintainer will get that change in sooner that later so others don’t have to bother!

Note: Someone commented that the line numbers listed were a bit off from version to version of Debian. Not entirely unexpected. It’s the change to calling the class directly that counts.