How is Multiple streams initiated?

[Patrik_J_L]

Hi,

I'm wondering how the multiple streams is initiated? For example is stream 1 always initiated first?

The reason for my question is that I'm developing some bpstart and bpend scritpts. 

I use the STREAM_COUNT and STREAM_NUMBER variables to have the last stream finished run some stuff in the bpend script, but I'm having problem when some streams does not start, for example due to backup window issue (196).

I was thinking on doing some "magic" when stream 1 is started and let the rest of the streams just wait until the "magic" is done, but I need to be sure that stream 1 is started first.

TIA

Patrik

[RiaanBadenhorst]

Hi,

Yeah its quite messy. I tried it once, but i'm no programmer. I tried the logic of creating a file to test for and placing the stream number in the file.

BPSTART

If the file is not there you're first, add 1 to the file. Run the Magic

If the file is there, replace the stream number with yours, move on, etc.

BPEND

Check the file, check the stream number, decrease it by one, move

Check the file, if its one stream left, remove file, run magic.

But then, I'm no programmer

And you have to contend with streams possible starting at the same time and both (or more thinking) they're first....

[Patrik_J_L]

Hi,

Thanks for your comments.

One problem in your structure is if all streams has not been started before the last active one is finished, the "bpend" magic will be done before all streams are executed. And there is more issues as well.... 

I would really like to know about HOW the streams is initiated since it would help me if I always can have stream 1 doing all bpstart magic.

/Patrik

[RiaanBadenhorst]

Ah yes, i remember that now. Knew there was a reason it sucked (My logic that is :P).

Sorry, can't comment on the order of the streams, i think its quite random.

[Andy_Welburn]

parent_start_notify & parent_end_notify scripts?

[RiaanBadenhorst]

Andy's right.

Those would work great if they ran on the client and not the master. Suppose if its UNIX it wouldn't be a problem to remote execute, Windows is a little more tricky (IMHO).

[Andy_Welburn]

it does depend on exactly what you want to achieve & where...

Oh, & how much effort you want to put in to get there!

[Patrik_J_L]

Hi,

Parent_start_notify & parent_end_notify scripts would have been perfect. Unfortunatelly, we are not allowed to use remote execution in this environment :( 

[Yasuhisa_Ishika]

not suitable for any tasks. Jobs will not wait completion of parent_start_notify,I know.

[Andy_Welburn]

posted sometime back - I'll see if I can find it again, but don't hold your breath.

In the meantime, this is all that Symantec are willing to offer (altho' I get the feeling you've already come across it!):

Implementing the NetBackup bpstart_notify and the bpend_notify scripts when using Multistreaming in the backup policy
http://www.symantec.com/business/support/index?page=content&id=TECH69986

[Patrik_J_L]

Hi Andy,

Yes I have seen that one. One of my concerns is that I need to be sure that all streams has been executed successfully because it is a DB I'm backing up.

That suggestion will not see if some streams where never started due to a close of backup window issue for example. I must add some control of the number of streams executed using the STREAM_COUNT, but if all active streams is done and the other ones are never started, I would have a DB that is not started again.

The script is getting quite complex after a while.

Regards

Patrik