Opinions: root mirror recovery

[Stuart Remphrey - Sun Computer Systems SE - QLD Australia]

Richard/Robert,

Some sites do use DiskSuite for system disk mirroring, and SEVM
for the rest.  You still have to put rootdg somewhere (preferably
*not* where your data is!)  With SEVM the system disk pair does
provide a nice place for rootdg, but if DiskSuite fouls up at
least you can see where the unmirrored partitions are, some sites
like the simplicity.  On the third hand, then the sysadmins have
to learn an extra volume manager.

There's really no universal law either way...

Stuart.



` Robert.Cross@scottish-newcastle.co.uk writes:
` > We have an E4000 here with an attached SSA114, running Volume
` > Manager 2.6. Now, for resiliancy/performance reasons I've
` > encapsulated and mirrored the root volume, one copy on a SCSI
` > disk tray, and another on the SSA itself.
` > 
` > Talking to one of our Disaster Recovery suppliers yesterday,
` > and he was saying that he's been told that if the root volume
` > gets trashed, it's very difficult to recover the system if the
` > root volume is under VM control. He's further been told thatu
` > it's actually better to install DiskSuite from the Solaris 2.6
` > CD,> and use THAT to mirror the root volume.  The problem with
` > VM is that apparently to recover rootvol you need to know what
` > the low level organisation of the disk is. This information was
` > given to him by a lecturer on a Sun Volume Manager course he
` > attended recently.
` > 
` > Has anyone out there got any experience or opinions one way or
` > another on this?
` 
` 
` Yow, I hope not! We run SSAs and A5200s with root in the arrays under
` VM control... however, we do separate root (and swap where we have
` swap disks rather than files) from any other stuff in their own
` disk groups. Normally, we have SSAs which are in separate locations
` and are (bootable) mirrors of each other, for resiliancy. I wouldn't
` be at all keen on mixing SEVM with ODS. The above sounds like a
` misunderstanding, not casting aspersions on anyone....  however, I
` do like to keep root and [anything else] in their own DGs.
` 
` 
` > The information contained in this message and any attachments:
` > [ ... snippety snip ... ]
` 
` Crikey, your legal dept. must've been on overtime!  I wouldn't
` send that lot to any usenet group without a clean set of the
` old asbestos underwear!!
` 
` 
` HTH.
` 
` Richard.
` -- 
` The Open University is not responsible for content herein, which may
` be incorrect and is used at reader's own risk.



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