My 2 cents on SSO (very short)
If you have to do it and say you have 200
servers with about 40 drives I recommend you set it up as:
50 servers per 10 drives.
That way you have a few drives to spread
across but you don’t have the headache of maintenance that you would with
200 servers on 40 drives.
Dom
From:
Curtis Preston [mailto:cpreston AT glasshouse DOT com]
Sent: Wednesday, 30 January 2008
12:24 PM
To: Dominik Pietrzykowski; Veritas
NetBackup; veritas-bu AT mailman.eng.auburn DOT edu
Subject: RE: [Veritas-bu] What's
Best Practice for SSO in NBU 5.1
Here’s my
thoughts. If a server is too big to back up over the LAN, then make it a
LAN-free server. As to how many server you should MAKE LAN-free and have
share a single drive, I’d say that depends. Let’s say that by
moving a group of servers from LAN-based to LAN-free, each server’s
backup now takes only 2 hours instead of 12. (totally feasible).
Let’s also say that you have a 12-hour backup window (also totally
feasible). I’d say that six server with a 2-hour backup window each
can share a single tape drives. Now let’s make it 20 tape drives
with 120 servers, each with a backup duration of 2 hours. I don’t
see any problem with this configuration. OK, I am pushing the 12-hour
window and I didn’t leave any room for error. So let’s make
it 100 servers and 20 tape drives, or 200 servers and 40 tape drives, each
server with at 2-hour backup window. I have no problem with this
configuration.
Where the math of big
numbers is really in favor of such a config is when their full backup takes 6
hours, but the only need to do that full backup once a month. Every other
day of the month they do an incremental that lasts only 15 mins.
Let’s say we have 1 tape drive and 12 hours to use it. 21
systems can now share this tape drive with time to spare. Each night, it
will do a full backup one of them, and the incremental backup of the rest.
That’s 6 hours (for the one full backup) and 5 hours for the other
20 incrementals (15 x 20 / 60), and we’ve got time to spare. With
that kind of math, 200 systems can share 10 tape drives NO PROBLEM.
Should you do it?
Why not. You’re fully leveraging your infrastructure. Especially if
by moving those servers from LAN-based to LAN-free you’re now streaming
the drives. They’ll be happier and last longer.
From:
Dominik Pietrzykowski [mailto:dominik_pietrzykowski AT toll.com DOT au]
Sent: Tuesday, January 29, 2008
4:52 PM
To: Curtis
Preston; Veritas NetBackup; veritas-bu AT mailman.eng.auburn DOT edu
Subject: RE: [Veritas-bu] What's
Best Practice for SSO in NBU 5.1
Does not mean it’s a good idea. You
should only do it if you have to IMO.
From:
Curtis Preston
[mailto:cpreston AT glasshouse DOT com]
Sent: Wednesday, 30 January 2008
10:02 AM
To: Veritas NetBackup;
veritas-bu AT mailman.eng.auburn DOT edu
Subject: Re: [Veritas-bu] What's
Best Practice for SSO in NBU 5.1
I’ve seen hundreds.
From:
veritas-bu-bounces AT mailman.eng.auburn DOT edu [mailto:veritas-bu-bounces AT mailman.eng.auburn DOT edu]
On Behalf Of Veritas NetBackup
Sent: Tuesday, January 29, 2008
12:50 PM
To:
veritas-bu AT mailman.eng.auburn DOT edu
Subject: [Veritas-bu] What's Best
Practice for SSO in NBU 5.1
Anyone has good idea what's maximum Number
of Media Server we can share tape Drive using SSO.
I have seen SSO Drives Shared among 20 Media Servers,
35 and 45 Servers. I'm just curious to know.