ADSM-L

Re: Library out of space. Time for disks?

2006-10-19 22:31:23
Subject: Re: Library out of space. Time for disks?
From: "Prather, Wanda" <Wanda.Prather AT JHUAPL DOT EDU>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Thu, 19 Oct 2006 22:30:21 -0400
Been there, done that.
 
- Advantage of building your own pool is that you can expand it whenever you 
want just by adding disk.
CDL's on the market mostly have an upper limit on the TB they support.
 
- You'll need to pre-allocate the volumes as mentioned before, but that's easy 
if you use the new 5.3 options on  DEFINE VOLUME as mentioned in previous post.
 
- Disadvantage of using your own pool is that the CDL's have built-in 
compression, like the tape drives do.  Slows down the throughput a bit because 
it's done in software, but at least it's done outboard of TSM.  So if you build 
your own pool, you'll need to plan on doing your compression on the client end.
 
 
 

________________________________

From: ADSM: Dist Stor Manager on behalf of Orin Rehorst
Sent: Wed 10/18/2006 2:58 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: Library out of space. Time for disks?



I could use an external drive rack, build a RAID array, and use it to
replace my primary tapepool, correct? What would be the disadvantages of
that vs. a VTL?

TIA
Orin Rehorst

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
Thorneycroft, Doug
Sent: Monday, October 16, 2006 10:18 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: Library out of space. Time for disks?

That's what we are doing. Our primary is a 6.4 TB VTL.
So far, it's working very well. Excellent performance.

Main concern is if the device fails, how long will it
take to restore all those terabytes of primary storage
from offsite volumes.


-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU]On Behalf Of
Orin Rehorst
Sent: Monday, October 16, 2006 8:02 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Library out of space. Time for disks?


Our IBM 3583 tape lib is out of space.

What do you think of this idea?

Acquire disk-based appliance i.e. 3 TB. Use it for primary. Use 3583 for
off site tapes only.

Please advise.

TIA

Orin Rehorst