Robert J. Phillips wrote:
>
> I trust Raid 5.  We have a mail server that has Raid 5 and twice we have 
> lost one of the drives and been able to get the new drive, put it back 
> into the Raid and let it rebuild with no down time except the time to 
> put the new drive in (20 minutes). 

Raid5 works, but has a serious efficiency cost on writes - and can be 
extremely slow in degraded mode with a bad drive (where raid1 continues 
at full speed).

> Something else I learned about Raid 5 and 6 from my research into a 
> Blade server and a SAN is that the more drives you have in your Raid it 
> increases that bandwidth (throughput) of the data letting everything 
> work faster.

Yes, if you have about a dozen drives in the array it starts to look good.

> I don’t necessarily consider the loss of the BackupPC data a 
> catastrophe.  I could see how it could be for someone that really wants 
> to keep archive copies of backups.  If we have a total failure of 
> BackupPC we would rebuild it and start backing up again.  I guess the 
> worse scenario would be something that would not only hurt our BackupPC 
> server but also damage several other servers at the same time. 

The question here is what will happen after a site disaster.  Will you 
collect your insurance and retire or go into some other line of work or 
will you have to reconstruct your data and continue as best you can?

> The question comes down to each individual and how much time can you 
> afford to rebuild the data.  Is that downtime worth the extra money to 
> put in more redundancy in the drives, offsite solutions or clustered 
> servers.
> 
>  
> 
> There are so many options but they all have a positive and a negative 
> and I don’t think any solution, no matter how much money you have, is 
> 100% failsafe.  The odds of not being able to recover may be small but 
> it is still there.

In many cases the simple solution is to run a completely separate 
instance of backuppc in a different location that picks up the critical 
data, perhaps over a vpn connection.  This eliminates any singly point 
of failure and doesn't take much extra ongoing work.  If that isn't 
practical, making image copies of the archive might work.

-- 
   Les Mikesell
     lesmikesell AT gmail DOT com



------------------------------------------------------------------------------
OpenSolaris 2009.06 is a cutting edge operating system for enterprises 
looking to deploy the next generation of Solaris that includes the latest 
innovations from Sun and the OpenSource community. Download a copy and 
enjoy capabilities such as Networking, Storage and Virtualization. 
Go to: http://p.sf.net/sfu/opensolaris-get
_______________________________________________
BackupPC-users mailing list
BackupPC-users AT lists.sourceforge DOT net
List:    https://lists.sourceforge.net/lists/listinfo/backuppc-users
Wiki:    http://backuppc.wiki.sourceforge.net
Project: http://backuppc.sourceforge.net/