ADSM-L

Re: EMC CELERRA backup options - need feedback

2005-09-09 08:24:05
Subject: Re: EMC CELERRA backup options - need feedback
From: TSM_User <tsm_user AT YAHOO DOT COM>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Fri, 9 Sep 2005 05:23:49 -0700
If you haven't tested a CIFS backup I suggested you do that first. It works of 
course but is much slower.  We compared CIFS backups through a windows server 
of 1 million files to a backup of 1 million files on the Windows server itself 
and it took 10 times as long to scan through the directories on the CIFS share. 
 There is little difference in speed for the first incremental backup because 
the NIC is the bottleneck in most cases there.  But on the 2nd day when your 
used to the incremental backup scanning through the system at between 1 million 
and 2 million object an hour it will instead run at between 100,000 and 200,000 
objects an hour. So if you have a CIFS share with 2 million files it could take 
up to 20 hours to just run a regular incremental backup with no data changing.  
 
When we first saw this problem 2 or 3 years ago we had a call open with MS, 
Tivoli and EMC.  In the end we were told by MS that calls to files and their 
attributes on remote shares are tuned differently than calls to local file 
systems.  I don't remember all the specific "whys" but the main thing I do 
remember is that they said it was "working as designed".
 
We've found that if you have small CIFS shares backing them up through a 
Windows server is best so that we can get the granular backup you want.  If 
they are large then you have to use NDMP.  In at least one case I have a 
customer that choose to backup the Windows data through a Unix server.  They 
loose the permissions but because they secure everything at the folder level 
they just wrote a script that uses XCACLS.VBS.  They use the unix server to 
perform the recovery and then run the XCACLS.VBS program from a windows server 
to set permissions. 
 
Kyle

"Waldon, Jo" <jo.waldon AT EDS DOT COM> wrote:
Setup a baclient for each volume or however you want to back it up on
another server (i.e. W2k or w2k3) - also setup browsers for each to
enable restores.

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
Zoltan Forray/AC/VCU
Sent: Friday, 9 September 2005 1:55 a.m.
To: ADSM-L AT VM.MARIST DOT EDU
Subject: EMC CELERRA backup options - need feedback

I am looking for information/guidance/suggestions/sanity-checks on my
current project involving backing up an EMC CELERRA NAS.

Originally, I was told to approach this as an NDMP backup. The more we
look at the drawbacks/limitation of TSM NDMP backups vs what we need to
be
able to do with the backups, we are looking at alternative methods for
backups.

Our scenario for the NAS is going to be like this:
1. 300GB to start - up to 3TB.
2. Multiple different clients, both real servers (Windows and *NIX) and
"virtual server" connections
3. Lots of workstations connecting to the NAS via AD group
policies/"virtual server mountpoints" to redirect their "My Documents"
to
the NAS.

We need granularity of control over who can restore what from the TSM
backups. The NDMP method doesn't seem to be able to handle this.
We need to perform offsite backup copies (i.e. DR, audit requirements)
which the NDMP method makes painful (snapshots......backing up twice).

So, how do you backup your CELERRA ?

                
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