[CentOS] How to copy a system?

[Dag Wieers]

On Thu, 5 May 2011, Les Mikesell wrote:

> On 5/5/2011 11:11 AM, Lamar Owen wrote:
>>
>>>> I do dd imaging quite frequently, and as long as everything is LBA48 capable and setup, [snippage] .... using dd .... booted from rescue or live media of the OS that's installed...
>>
>>> Clonezilla-live is a handy, faster way to do this.
>>
>> I've recast my original message slightly, as you've missed a critical point: I use the cloning tool from the rescue or live media of the OS that's installed.  There are a number of reasons for this, not the least of which is that LVM, RAID, and some other things behave differently depending upon the kernel, lvm tools, etc, that's running the clone.
>
> I generally try to avoid layers that are likely to have breakage between
> different versions.  Backwards compatibility is a good thing, as is the
> ability to move disks around among different hosts.
>
> That said, Clonezilla doesn't deal with software raid in the disk image
> mode - even raid1 where it should be simple.  You can do single
> partitions at a time though, and then it is agnostic about the
> underlying layers but you have to deal with making it bootable yourself.

I can recommend ReaR (Relax and Recover) for migrations and cloning 
systems. I have been working wit the Relax and Recover project for the 
past few months together with a colleague and it now covers a lot of 
situations:

  - HWRAID (SmartArray), SWRAID, DRBD, partitions, encrypted
    partitions, LVM

  - It supports bootable tapes (OBDR), ISO images and USB media

  - It supports backup software for restoring (like Bacula, TSM, rsync and
    others)

  - And it can also take care of backups (using rsync, tar) using different
    solutions (NFS, USB, Samba, ...)

  - It's modular, so with little effort you can implement your own workflow
    or use-case

However I would stress to test a complete disaster recover scenario for 
your systems (different technologies) in order to understand if everything 
is supported. You don't want to realize a problem in disaster-mode :)

But for the use-cases we have, the current trunk is very usable and 
flexible to support restoring on different hardware. Even with different 
controllers/disks etc... During recovery you can still adapt the layout 
and make changes to your wishes before restoring.

We are preparing a new stable minor release (without the new layout code 
enabled by default), but after that release there should be a new major 
release covering everything I mentioned by default.

If you need more help, feel free to join the ReaR mailinglist on 
sourceforge and ask your questions :)

     http://rear.sourceforge.net/

And if you happen to go to LinuxTag, we're having two discussion sessions 
for developers and users on Wednesday and Thursday.

-- 
-- dag wieers, dag at wieers.com, http://dag.wieers.com/
-- dagit linux solutions, info at dagit.net, http://dagit.net/

[Any errors in spelling, tact or fact are transmission errors]