[CentOS] running yum update on remote servers

Mon Feb 25 13:48:48 UTC 2013
Robert Moskowitz <rgm at htt-consult.com>

I have read a couple old threads here on updates for servers, and I am 
looking for some mechanics to getting the actual updates done.  I don't 
want automatic updates; I want to control when and what gets updated.

First I have to determine that a particular server needs updates.  I 
suppose a daily script that would run "yum check-updates' and emails me 
the results could work, but then I would only want the email IF there 
was something to update, at my limited use of this option does not show 
anything to trigger a notify on changes.  Does anyone know of a script 
that would do this?

Then there is the actual update.  I learned long ago NOT to run yum over 
an SSH connection, as WHEN that connection breaks in the middle of an 
update, you can have quite a problem to clean up.  All I have done 
todate is to start vncserver and connect via vnc to then run yum.  I can 
even drop the vnc connection and come back later to check results.  I 
have considered running yum disconnected (? when you end a command with 
&) and log the results to a file that you check later.  What are 
practical approaches to this?  I only have a few servers here to manage.