Networker

Re: [Networker] Best usage of tape drives

2005-10-25 17:16:44
Subject: Re: [Networker] Best usage of tape drives
From: "William M. Fennell" <William.Fennell AT CHANNING.HARVARD DOT EDU>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Tue, 25 Oct 2005 17:15:33 -0400
Thanks Darren,

In jbedit it asks if the tape drive will be shared. I thought that meant two drives could work together to save large data sets faster than one drive working alone. However it might mean sharing the tape drive between
two hosts, which wouldn't apply to this situation.

Bill

--------------------
William M. Fennell
UNIX Administrator
Channing Laboratory



Darren Dunham wrote:

My issue is that it only uses one drive! So it is trying to write 200+GB
nightly from three file systems on this host to one tape.
How can I make it use both tape drives? Currently it is taking about 8 hours to backup about 200GB nightly to one drive.
I would like to improve on that performance.

My two ideas are:
1: reduce the number of target streams on each drive to two and then
have one drive take two streams and the other take one stream.

That's probably a good idea, but you'd want to test it.  You might also
try running a single stream to each drive (let the 3rd stream wait until
one of the other 2 are done).  Whether that's faster would depend on
what's getting maxed out during a single-stream backup.

2: Maybe the drives need to be shared with each other?

I'm not sure what you mean here...



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