Taylor,

We are asking ourselves the same question:
is ADSM really a backup product designed for clients with big disks (more
than 10GB)?

We are facing exactly the same problems plus one: the restore of ONE file
coming from a large disk.
In 95% of the cases, the "client" need the -1 backup version:
User mistake occurs in file-a on a large disk of an NT file server on
day-one,
incremental backup occurs during night day-one to day-two,
the client understand his mistake on day-two and ask Help-desk to restore a
backup version of day-one
Help-desk try to : RESTORE -INACTIVE -TODATE=day-one file-a
....... and he waits 2 TO 6 hours to receive an answer from the server.

The solution we intent to install:
Put all the large NT-servers disks on EMC,
Use FDRSOS on MVS to backup directly those disks to robot cartridges.
And use ADSM for the "small" disks (<10GB).

Server: ADSM 2.1 L 0,6 on MVS
DB: 28GB, 18.000.000 entries in the DB, 2 TB backup data on 3490 cartridges
Disk backuppool: 14GB will extend to 17GB
CPU consumption: HUGE (more than DFhsm)
Clients: NT (55), AIX(10), DecAlpha(8) all  ADSM 2,1

V3 will sure be better, V4 more better, V5 more more .......... is not a
good answer for the final user that is waiting on the restore of the
version -1 of ONE file.


Francis.


-----Message d'origine-----
De : Taylor Mitchell <taylor_mitchell AT MSN DOT COM>
De : Taylor Mitchell <taylor_mitchell AT MSN DOT COM>
À : ADSM-L AT VM.MARIST DOT EDU <ADSM-L AT VM.MARIST DOT EDU>
Date : jeudi 23 avr. 1998 4:13
Objet : Large ADSM Restores


>While much of the discussion in this forum has focused on backup
performance
>issues, another issue that is perhaps even more important is restore
>performance.  In particular, as servers have become more powerful, have
>become consolidated, and larger amounts of disk media are attached, the
>implications of a media failure become more serious.  For example,
depending
>on the average file size, the cpu speed of the client, and the network
>connectivity, the time to restore a larger(e.g. 24 GB) RAID storage device
>could  be several hours or even more than one day.  If you have never gone
>through the exercise, I would encourage you to restore the contents of a
>entire raid storage unit to a test server.  You may be surprised how long
>this can take, especially if there are lots of small files.
>
>I'd be interested in hearing from on others on the methods others have used
>to mitigate the risk of an extended outage due to long restore times that
>could be encountered if an entire raid storage unit failed.
>
>For example, limit the amount of storage that can be attached to a single
>server?
>
>Create prioritized plans to restore "important" data first?
>
>Limit use of ADSM to clients below a certain size?
>
>Thanks in advance,
>
>Taylor
>