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H_Sharma's avatar
H_Sharma
Level 6
10 years ago

Media Multiplexing

Hello Experts,

We have set Media Multiplexing value 4 in policy and in storage unit it is set as 16. I ran nbrbutil -listActiveDrivejobs Drive001 and found there are 5 jobs running. Then i checked in other drives and found all are drives are writing 5 jobs.

So i need to know why these are 5 jobs not 4 as we have set Multiplexing as 4 in policy.

Thanks,

 

  • You need to have a look at MPX in schedules of ALL policies. (So far you have mentioned policy (which means only one policy to me).)
    You say above: these 5 jobs are from differnt policies.

    We also need to know ho many active jobs - bpbdbjobs |grep -i active (not just amount of active drives).

    If there are 5 clients, there will be a minimum of 5 active jobs for the one policy. One per client. 
    MPX will make more than one job go to the same drive, not have less jobs.
    Now you also need to look at the policies of the other active jobs.

    If 1 policy has MPX of 1 and another policy has mpx of 4, then the lowest value (1) will override the higher value.
    Same for schedule mpx and STU mpx - the lower level overrides the higher level.

    Other factors that play a role is the volume pool specified in the policies and retention levels in the schedules of the different policies.

    Have a careful look at these 2 links:

    About Multiplexing: http://www.symantec.com/docs/HOWTO86804 

    Example of using multiplexing with schedule: http://www.symantec.com/docs/HOWTO86888 

    Hopefully comparing the diagrams in above URLs with your own config and active jobs vs active tape drives seen in your environment will help to clear any doubts.