|
I use DSUs for network media servers and
either DSUs or VTL for large clients that need to be dedicated media
servers.
Here are some things to consider with network based
backups:
Using VTL: A slow network client will hold onto a VTL
tape. The other images on that tape are then not available for duplication which
means if there was a data center disaster those images would not have been
copied to tape yet. This impacts your RPO.
Using DSU: A slow client will only effect the
duplication of its image and not the image of other
clients.
I use VTL on large clients to save
money.
Under a DSU methodology I must allocate the san storage
directly to the host in a multiple of the size of prod disk
space.
As the prod space grows the DSU space needs to grow.
This must be monitored, managed, and sustained. There are hundreds of
these types of clients across many data centers.
In addition, that allocated DSU space is not available
for any other media server so there is a lot of unused, yet allocated storage,
and with no compression.
With VTL I can put that head in front of the same
storage and zone the virtual drives to the media servers. The VTL arbitrates the
access and provides a shared storage resource accessible over a high speed
SAN.
I have the ability to increase backup storage capacity
without touching a production client.
In
addition I get compression on that storage.
__________________________________________
Jonathan Marianu
(mah ree ah' nu)
AT&T Storage Planning and Design Architect
(360)
597-6896
Work Hours 0800-1800 PST M-F
Manager: Jim Taylor
(dt3249)
(678) 893-3170
_______________________________________________
Veritas-bu maillist - Veritas-bu AT mailman.eng.auburn DOT edu
http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
| 