Handle DNS errors and other network failures

[deoren]

Output sent to me via cron email:

/etc/cron.daily/email_updates:

https://cdn.redhat.com/content/dist/rhel/server/5/5Server/x86_64/cf-tools/1/os/repodata/repomd.xml: [Errno 4] IOError: 
Trying other mirror.
https://cdn.redhat.com/content/dist/rhel/server/5/5Server/x86_64/rhev-agent/3/os/repodata/repomd.xml: [Errno 4] IOError: 
Trying other mirror.
https://cdn.redhat.com/content/dist/rhel/server/5/5Server/x86_64/os/repodata/repomd.xml: [Errno 4] IOError: 
Trying other mirror.
SQL error: near "Temporary": syntax error

The email notification contained a body that looked like this:

-3,-'Temporary
 


Hostname: X.X.X

IP Address(es):
----------------------------------
X.X.X.X

My first thought is that this situation should be treated the same as if there were no updates at all and not reported. Or at the very least let cron catch the errors and skip sending an email notification. That way whatever ticketing system that catches the emails won't create invalid tickets.