Re: 3000 clients bkp to TSM?

On Tuesday 27 May 2003 16:27, Pothula S Paparao wrote:
> Hello TSM'ers,
> I have 3000 clients (each 5GB approx) backup proposal to TSM server.
> Expecting 600 to 1000 clients fire their  backup to TSM concurrently.  Can
> TSM able to handle all these session fired at a time ? If not , how to
> handle all my client to initiate their backup to TSM in 6Hours backup
> window time.
> Note : Network team already worked on the above solution and  given green
> signal saying they dont have any problem.

Sreekumar,

That's going to be a *very* busy TSM server...

Even if you can spread the load perfectly evenly across the 6 hour window it's
going to start a new session every 7.2 seconds... Assuming each session lasts
on average 10 minutes, that's 83 concurrent clients at any one time for the
entire 6 hours. Wow.

Can you spread the load across multiple TSM servers?

Are *all* the clients simply B/A filesystem clients? No TDP clients, no SAN
attached clients?

Are they all located at one site? If not, have you considered using a TSM
server at each site?

You could use "client polling" schedule mode with "randomization" to stagger
the scheduled startup time, but I think you'd probably be better off using
"server polling" schedule mode and "max sessions / max scheduled sessions" to
throttle the number of concurrent clients. Possibly also use multiple
schedules to group the clients within the 6 hour window.

If these are Windows clients you might consider using the Journal backup
service to reduce the load on the server during the client session startup.

Have you thought about the TSM database size? I just did a quick calculation
(assuming 100 kb average file size, 35 versions retained, 5% daily change
rate, etc) and your TSM database might end up about 400 Gb in only the first
month or so. That is (practically) impossible. This leaves you little option
but to split the load across multiple TSM servers.

You'll also need significant disk storage pools, and tape drives to handle
this load, plus copy pool creation, reclamation, migration, etc. Have you
considered using collocation. Scary... :)

Give me a call on the number below if you'd like to talk about your solution.

Regards,
Steven P.

--
Steven Pemberton                             Mobile: +61 4 1833 5136
IBK (Senetas)                                Office: +61 3 9820 5811
Senior Enterprise Management Consultant      Fax:    +61 3 9820 9907