Veritas-bu

[Veritas-bu] multiple streams/ALL_LOCAL_DRIVES/slow restores

2002-05-31 15:51:32
Subject: [Veritas-bu] multiple streams/ALL_LOCAL_DRIVES/slow restores
From: sgiessle AT wvu DOT edu (Steve Giessler)
Date: Fri, 31 May 2002 15:51:32 -0400
Hi,

I'm new to Netbackup and need a few pointers if someone would be so kind.

I have NB version 3.4.1 running on a Windows 2000 box. I have a 
Cybernetics 15 tape robotic library connected to that box with a 
single SONY SDX-500C drive in it (uses 50 gig native AIT2 tapes).

I have three Solaris 8 clients that I want to backup. I want them all 
to multiplex to one tape in as many streams as possible at one time 
(8 seems to be the limit). My understanding is that if I choose 
ALL_LOCAL_DRIVES, and have multiplexing and allow multiple streams 
selected (which I do and both are set to 8), then each mount point 
will initiate a separate network stream of data to the drive and up 
to 8 streams will backup concurrently.

Is this correct?

If so, it is not working this way. What I get when I start a backup 
is this: The mount points are each "Queued" and only one stream is 
started from each host. When the single stream on a given host is 
finished, it begins the next queued mount point on that host. 
Shouldn't it be able to stream multiple mount points at the same time 
from a single host?

In any case - each of my 3 Solaris client machines contains at least 
3 hard drives in them - each with separately mounted partitions and 
mount points on each drive. So, at a minimum, I see a potential for 9 
streams right there. Why then, when I run a backup, can I only get 2 
streams at a time to run and not the desired 8? . This way it will 
take forever to backup all that data.

Another question I have is in regard to the ALL_LOCAL_DRIVES directive:

It seems that when I do a backup with the ALL_LOCAL_DRIVES directive 
selected, I am getting redundant backups. What I mean is when I do a 
full backup, each mount point gets backed up, and then when it backs 
up / (root) partition - it goes through and backs up all of the 
subdirectories under root also - in other words - all of my mount 
points - the entire file system gets backed up - twice in one full 
backup.

How can I prevent this? I don't want to have to manually tell it 
which directories to backup (never had to with Legato Networker).

I have used Legato Networker on Unix in the past and so far, I wish I 
hadn't switched, but hope that it is just my ignorance and needing to 
work out the details.

My last question is this: When I do a restore - it seems to read 
through the entire 50 gig tape in order to find the files that were 
selected to restore. With Legato Networker, the index files kept 
track of the position of the files on the tape and it would find and 
restore them very quickly (in 5 minutes or less usually). I tried 
restoring a few small files (200 K or so total) and it took about an 
hour for it to scan through the entire tape before it could find the 
files and restore them. Surely I must be doing something wrong. I 
have two catalog locations selected - one is the first tape in my 
library, and alternately a directory on my master server's hard disk.

Any suggestions greatly appreciated,

Thanks,
-- 

Steve Giessler, Unix System Administrator
West Virginia University
Eberly College of Arts and Sciences
201 Woodburn Hall
Morgantown, WV 26506
(304) 293-7855 x2214 or
(304) 293-2011 x2214

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