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Costas GeorgiouFlag for Australia

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Raid 5 Data Recovery Options and best practices for Backup

Hello experts

No the has a scenario last week where our clients server crashed, we use acronis to take incremental backups on to NAS.

The server had Raid1

we rebuild the raid with new HDD since the old died.
and then just restored the image on to one hdd and all done

Now the question

Had this been a Raid5 how would we have done it
since Raid 5 had data on to multiple HDD's we could not have been able to restore the image on to the HDD.

What is the best backup option for raid 5 and how would you restore it....?
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If this had been RAID 5 you can also specify a hot spare. So when one of the disc goes bad it would rebuild the array on the fly. As backup for RAID 5 I do a server backup. If I had to do
a restore I can do a bare metal restore. I will need to setup the disc first.
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@ Works2011
   what u meant was that restoring image on to raid 1 is easy ...u can attach the HDD to any machine and just restore the image on to the HDD.

But since raid5 uses multiple disks u can't restore the image by attaching to another machine....

please forgive my ignorance..i an a newbee hence all these questions...
I think you may be confusing disk and RAID and how it's presented to the operating system.

We're got multiple servers with different RAID levels (RAID1, RAID5 and RAID10), and yet all of these upon a critical failure restore exactly the same. The operating system is kept ignorant of the underlying disk architecture and sees a RAID5 array of fourteen drives as a single hard disk.

Your backup software doesn't (or shouldn't) care about the underlying hardware - it's sole job is to restore the data where you tell it to restore it. This may differ is you're doing full bare-metal images, as some operating systems (I'm looking at YOU, Microsoft Windows!) fail in interesting ways if the storage driver and interfaces change.

So, back to the original question, how to back up. Like most of computing, it depends. How fast do you need to restore data? How much data is acceptable to lose?

My generalized recommendations are thus:

Do full backups daily if you have both the storage space and the time window to do so.
Do full backups on Friday and differentials all other days if a full backup daily is impossible.
Do full backups on Friday and incrementals all other days if you have to.

I'm not a fan of incremental backups, but that's mostly because I come from an era where backups were done to tape and tapes had a (relatively) high failure rate. If you're able to do backup to disk to tape (B2D2T) I can't see why not to do incrementals.
@ MidnightOne

   Sorry but i do understand the question is little confusing...

Lets keep it simple

1) Raid 5
2) i have full image of server using acronis
3) server fails
4) we rebuild the raid with no data on it
5) ?
6) ?

where do we start from
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I've requested that this question be deleted for the following reason:

not sure if i was able to explain the questions as answers where way out of what i was after.<br />Thanks