[CentOS] Re: Migration from RH9

Thu Nov 22 17:48:26 UTC 2007
Ugo Bellavance <ugob at lubik.ca>

James A. Peltier wrote:
> Leonel Nunez wrote:
> 
> I can second this.  I am in the process of migrating 5 research labs 
> from Suse 10.0 to CentOS 5 (for various reasons).  The migration has 
> been in testing phase for over 3 months and a lot of bugs have been 
> found and corrected in that time.
> 
> A migration from any OS to another is a very tedious and time consuming 
> step.  You will need to work on each part of the migration individually. 
>  Start with the services that you are most familiar with or that you 
> feel you could learn the quickest.
> 
> Setup a machine with CentOS 5 and begin testing that service.  When you 
> are confident that said service is operating as it should, shift that 
> service from the production server to your testing server.  Let it run 
> there for a bit because chances are you'll find bugs and that will give 
> you a chance to fail the service back over (if necessary) while you 
> correct the issue.
> 
> Once you've gotten all the services over to the new box you'll be happy 
> to know you did it the "right way" and that you've incurred the least 
> amount of pain for you, your fellow workers who work with you and your 
> users.
> 
> IMHO, you should spend a lot of time testing the Perforce migration, 
> followed by your web services.  Migration of any SCM is a potentially 
> complicated operation.  I haven't used Perforce before, but be careful.
> 
> Secondly, careful testing of your web services is crucial.  You'll most 
> likely be upgrading version of Apache, PHP and libraries at the same 
> time which can break things like backward compatibility. Samba depending 
> on it's function within your institution would be a close third, if not 
> a tie for number 2, but that's up to you.
> 
> The squid services are probably not all that complicated if they're only 
> using a caching server (forward or reverse).
> 
> Of course, with proper software unit testing and a bit of elbow grease 
> I'm sure it will all go over well.
> 
> There are various papers on best practices for OS migrations and various 
> other system administrator task on the web just google for migration 
> best practices and you'll find lots.
> 

Wow, excellent advice!

Thanks!

Ugo