I am reposting this message as I was told that it appeared blank from the listserv.




Well, actually private volumes were never implemented on MPE/XL and MPE/iX.  They will not be implemented with the emulator.

What the emulator does support are volume sets and we are working to make multiple volume sets available with the emulator.  Our current thinking is that using volume sets, it would be very possible and easy to do massive backups of the volume sets at very high rates of speed with the attendant speed of recovery.  We are also testing the use of STDs to other volume sets for more surgical recovery options.

Private volumes died with MPE/V and they were never missed.

Denys

-----Original Message-----
From: HP-3000 Systems Discussion [mailto:[log in to unmask]] On Behalf Of [log in to unmask]
Sent: Thursday, September 29, 2011 10:34 PM
To: [log in to unmask]
Subject: Re: [HP3000-L] MPE on Intel hardware, thank you Stromasys

Dave,

Can't speak for others - but I've always considered it 'best practice' to divide your disk storage up into several 'Private Volumes'.  Why?  When a non-mirrored spindle in a PV dies, it only takes that PV out with it - allowing the rest of the machine running (unless the PV is the 'mpe_system_volume_set, in which case you're going to be doing a system install).  If it's only one of the data volumes that goes down - the 'system' is still up, greatly facilitating recovery.

If you can't afford arrays that protect the 'system' volume-set, at least you can get something (even if only Mirror/iX for RAID-1) to protect the data volumes.  And if you configure it properly -  RAID-1 is wicked-fast on reads, and pretty decent on writes.

Oh - and to answer your original question:  Yes, A400's can be set up this way.  At least, the ones I administer are setup this way.  The drives 'in the CPU chassis' are setup as "system volume set", and an external mirrored array is the 'data' volume.

Works great.  If the system volume goes down - data isn't likely affected.  If a mirrored drive fails - just swap it for a replacement.  This has gotten my client near 100% up-time for this system, for almost 10yrs now...

Hope this answers at least some of your question(s).

Brian Edminster
Applied Technologies, Inc
"Robust Solutions and Integrations,
   for Today, and Tomorrow"

Proud Sponsor of: www.MPE-OpenSource.org

* To join/leave the list, search archives, change list settings, *
* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *

* To join/leave the list, search archives, change list settings, *
* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *