Quick brief - for testing purpose, I installed puppet agent on 5 nodes (Debian Squeeze + puppet 2.7.20-1puppetlabs1), and puppet master on 1 server (same version).
On puppetmaster side in every manifest I check if $::osfamily == 'Debian'. Sometimes I also use $::fqdn, and check if it's not empty.
The problem is that every day on random hours I get mail from puppetmaster that he can't compile catalog for one of nodes. For example:
Fri Jan 18 19:18:24 +0100 2013 Puppet (err): Could not retrieve catalog from remote server: Error 400 on SERVER: Not supported osfamily at /etc/puppet/modules/system/manifests/skel.pp:20 on node mynodeX Fri Jan 18 19:18:24 +0100 2013 Puppet (notice): Using cached catalog Fri Jan 18 19:18:24 +0100 2013 Puppet (err): Could not retrieve catalog; skipping run
Another example, from puppetmaster logs:
Jan 15 18:58:49 monitor puppet-master: No fqdn at /etc/puppet/modules/system/manifests/motd.pp:29 on node nodeY
Of course after next puppet agent iteration, everything is fine. I have no idea how to find cause of this issue. Problem is common to all 5 nodes.
I'm 100% sure that it's not related to cron.