media multiplexing

[rilwan_dawodu]

Hi all,

I would be happy if you can help me out

What is the advantage of setting media multipexing to higher number over just putting it at 1.

This is urgent please.

regards

[MayurS]

Media Multiplexing will enable you to Run multiple backups at one time.

i.e. if there are 5 clients set to a pool say MULPOOL
and the media multiplexing is set to 5 then
when these backup s fire simultaneously they all will start writting to the same media at once.

But iif you set Media multiplexing to 1 then only one job will write to the media and others will wait in queue.

media multipexing to higher number is set when there are many clients to backup. & the time is limited for backups.

Hope this helps ;-)Message was edited by:
Mayur Shinde

[TempoVisitor]

Multiplex = multi jobs backed up at the same time on the same media
Multiple Data Stream = multiple backup jobs coming from the same client machine

Combination : let's say you have 4 luns of 100 gb each on your machine ... and only 1 tape drive.
Each of your luns can be read or backed up at 20 gb/hour
Your tape drive is SDLTfc and can support 80 gb/hour.

Without MPX nor MDS : to backup your client, you have 1 job of 400 Gb, working at 20 gb/h .... 20 HOURS !!!! If you have a problem after 19,30 hours ... all is failed.

MPX=4 jobs on the schedule and 4 on the STU.
MDS=One stream per lun ... Thats 4 streams
Max jobs per client=4 (host properties Master server)
The 4 luns send their data together :
Thats 400 Gb backed up at the speed of 80 gb/hour : 5 HOURS !!!!
And each of your luns has a dedicated job independant on the others.

MPX is intersting too with several client machines of course, but you will see that, if you win time at backup, you lose much more at restore.

[Mistyjean_Brown]

Why if you type in 4 in the media multiplexing when you go to run your full backup you get 8 showing up? Thanks!

[MayurS]

Why if you type in 4 in the media multiplexing when you go to run your full backup you get 8 showing up?

- This shouldn't happen.

In Media Multiplexing if i have Backuplist for client1 as
C:\
D:\
E:\
F:\
and i set the Media Multiplexing property to 4
then There will be seperate JOBS running for client1 backingup
C:\ D:\ E:\ and F:\ simultaneouly writing to the same tape.

How is your Policy defined ?

[Mistyjean_Brown]

Well it is just a standard policy that i am running a full backup once a week for the duration of 12hours. It is for one server. Thanks!

[J_H_Is_gone]

why when I click on the thread for ashly I get this thread instead?

[Will_Restore]

"Media Multiplexing

Ashleigh Stevens

“I have a example that I want to share about Media Multiplexing; PS-MPX - Policy Media Multiplexing                       TD-MPX - Tape Media Multiplexing Example TD-MPX = 30 Policy A -...”

See full discussion

Posted 19 hours 19 min ago by Ashleigh Stevens "

 

 The forum software seems to key off the title and then pick the first item which happens to be this old thread. :(

[David_McMullin]

If you have many hosts that are network based and can only output slowly, you can mutiplex them ( i had 12 on one drive once) so that it will drive the tape drive and prevent 'shoe shining'

Restores and duplications of these backups are terrible though.