upgrading from centos 5.6 to 6
 

how to upgrade from centos 5.6 to 6 ?

I would not advise an upgrade. For a server you should really reinstall it.

Ultimately you can just run "yum --releasever=6 distro-sync", but again, I wouldn't recommend it.

thx;
but my x-centos 5.6 server contains a lot of informations :gate-server;dns-server ;dhcp and others which manage our copany network

I wouldn't advise against upgrading it then. If it works, leave it.

i tried that command in centos 5.6 but not working?

well firstly, i advised against upgrading if you can't rebuild. Why do you want to??

secondly if something "doesn't work" you need to give useful information about what happened.

thx;
when i tried the command it tell me :
Command line error:no such option :--releasever but under centos 6 in other host the command run well.

---------- Post added 07-18-11 at 03:34 PM ----------

i want to update all my centos 5.6 packages to el6 centos 6 packages.

if you can not justify rebuilding a server, then you can not justify upgrading it. what if it doesn't work? upgrading is a BIG thing, just about EVERY package is replaced, and there is a high chance of things failing. Then where would you be?

under centos 5.6
yum update -y
no packages marked for update.

right, because you are still juston the release 5. If you really want to you can install the el6 centos-release package and run it again. Y M M V

i want to update my packages for securing my server

6.0 will be less sure than 5.6. The feature set is older on 5.x therefore had a lot longer to be fully security tested.

is it the same problem between redhat 5 and redhat 6?

it's the same packages, so yes. Each major release introduces new features, new code.... new bugs.

when we need update packages from centos 5.6 to centos 6 ,i need to reinstall my systeme to centos 6 and repeting all my server configuration

If you really want to upgrade, the proper way would be to:

1. Build up a test system and test the hardware.
2. Install CentOS 6.
3. Install the needed packages.
4. Configure it the way you need it.
5. Test it for a reasonable time period.

Then migrate the production system. Never make any untested changes to your production system, chances are high that you will fail.

Sorry, double post

you don't *NEED* to but if you are a professional systems administrator who takes their role seriously, then you would leave it or rebuild it.

Absolutely; there's a reason why RH does NOT support in-place upgrades across major versions ie 5.x => 6.x