Subj:Re: a what if disaster recovery question?
Date:1/6/2003 4:34:48 PM Central Standard Time
From:rb@telenor.net
To:DFinn@studentadvantage.com
CC:toasters@mathworks.com
Sent from the Internet



Daniel Finn <DFinn@studentadvantage.com> writes:

> What if we have a failure in one of the heads of our F760s?  We have a spare
> F740 head, would we be able to just put that in place?  Is the raid
> information stored on the disk or on firmware in the head?  I'm mostly
> wondering what would happen to the data in this situation. 

All relevant raid and firmware information is stored on multiple
disks, so swapping heads is simple and straitforward.

I have never swapped from a "larger" head to a "smaller" head, but
both heads are Alpha based, and it should work, atleast in theory, as
the HW is is more or less equivilant, but there are HW constraints on
max raw disk capasity, raw file system size, number of FC Host Bus
Adapters etc.  These factors may trip an apparent easy swap - though.

I have, on a couple of occations upgraded from F720 to F740 without
much ado. Only make sure to edit /etc/rc file ahead of shutdown.

We keep a spare head for our F740s, but since the major load now is on
F8xx (soon to add a FAS960c), we won't keep a spare F740 head on location
anymore - not really important ...

If disaster recovery is important, I would suggest a 'spare kit' or as
we do, service contract with a local agent with 24h delivery.

> Also, are shelves swappable between F760s and F740s?

Definitely yes, with or without disks

>>>>>>>>>><.rune

--
Rune Bakken              
Senior System Administrator   
Telenor Business Solutions (Nextra), ManagedServices/*/IP-Services
Ph: +47 992 86 474