[CentOS] Upgrade Question

Tue Jan 10 21:35:36 UTC 2012
m.roth at 5-cent.us <m.roth at 5-cent.us>

Les Mikesell wrote:
> On Tue, Jan 10, 2012 at 1:35 PM,  <m.roth at 5-cent.us> wrote:
>>
>>> We've got about 200 existing servers running CentOS/RHEL 5.6 and all
>>> new servers are being provisioned using CentOS/RHEL 6.1.  So that
>>> everything is consistent we need to upgrade the servers running
>>> CentOS/RHEL 5.6.
<snip>
>>> Any ideas???
>>
>> What we do is build one, then create /boot/new and /new on the next
>> server, rsync over to them, then mkdir /boot/old and /old, and (using
>> zsh with modules loaded) mv * old, mv old/lost+found ., mv
>> old/new/* ., make sure a few things are correct (for example,
>> ifcfg-eth*, /etc/ssh/), and sync, then reboot. All your other stuff is
>> fine....
>
> Have you looked at http://rear.sourceforge.net/ (and in EPEL) as a
> potential backup/clone/rollout mechanism?  It seems like something
<snip>
The one difference with the method we use is that you *don't* have to
format /, and so anything you have under it is still safe. We normally
have a few directories that are local, and so need to be saved (web, a
temp that everyone can use that is guaranteed *not* to go away, etc).

It's also pretty quick: you don't affect the running system while you're
rsyncing over, so then the rotation takes long enough to issue the few
commands, check grub and fstab, and reboot.

       mark