Networker

Re: [Networker] Disaster Recovery testing

2006-05-10 06:06:05
Subject: Re: [Networker] Disaster Recovery testing
From: Pascal Rijs <pascal.rijs AT UNILEVER DOT COM>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Wed, 10 May 2006 05:56:16 -0400
I've have successfully done several serious DR tests with my backup 
environment (Win 2000, Legato 6.1.4 and 7.1.1, HP MSL5000 series 
libraries). Successfully recovering 2 Sun Solaris, 1 HP-UX, 1 AIX and 16 
servers running several windows versions.

Our live systems run on HP hardware and our DR site has Dell hardware. The 
first thing to beware of is TCP/IP speeds and duplex FIXED on both server 
and switch, but secondly the BLOCKSIZE configuration on your scsi bus and 
within Legato. unix/linux tends to use 128k blocks by default (correct me 
if I'm wrong) and windows defaults to 64k blocks. This may explain DR 
problems when using a Windows box to restore a linux client.

You can use the following command on your legato windows box to check the 
scsi block size:

mt â??f \\.\Tape0 status (this allows you to check the maximum block size of 
the tape drive. When this is not 128k or above, you need to make a setting 
on the scsi adapter in the registry: 
HKLM\SYSTEM\CurrentControlSet\Services\<scsidriver>\parameters\device; add 
DWord MaximumSGList=FF)

The above text is applicable to our standard 128k block size; this may not 
apply to other environments.

Not having configured the same block size on your DR legato server as the 
tape were written with will result in slow performance, errors and even 
worse recovery failures.

To sign off this list, send email to listserv AT listserv.temple DOT edu and 
type "signoff networker" in the
body of the email. Please write to networker-request AT listserv.temple DOT edu 
if you have any problems
wit this list. You can access the archives at 
http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER

<Prev in Thread] Current Thread [Next in Thread>