From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On
Behalf Of Todd Lundstedt
>I am just trying to consider all the pros/cons of having multiple copy
>storage pools per primary pool. I was considering having one
>copy storage
>pool that never gets taken offsite (remains in the library),
>and two copy
>pools that get checked out and set to "offsite". Obviously,
>the pros are
>that, in the event of a disaster, you have multiple offsite
>storage pools
>offsite, and volumes that are destroyed, damaged, or lost in transit to
>your recovery center are duplicated in the storage pool set
>that remained
>offsite. Additionally, the onsite copy storage pool can be used to
>restore damaged primary storage pool tapes.
Con #1: You are trying to cover a triple failure--the failure of the
client, the failure of the primary pool tape(s), and the failure of the
first offsite tape pool tape(s). I daresay that no one reading this list
has ever run across the need for that much coverage in a system that is
properly maintained and monitored.
Con #2: (At least) 1/3 more space reclamation and storage pool backup
resources needed
Con #3: (At least) 1/3 more money spent on media, and the handling
thereof
I just don't see the need. In this professional's opinion, that is
spending far too many resources to cover eventualities that will never
see the light of day. As I have commented before, in the 11+ years I
have dealt with ADSM/TSM, I have not experienced a single byte of data
loss in a system that has at least one properly maintained primary pool
and one copy pool.
--
Mark Stapleton
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