Oracle Channels

[tsmdumber]

Hi

Is the number of channels allocated in the rman script equal to the no of simultaneous sessions that will occur during backup? ( something similar to maxresourceutilization ?)

If thats the case the data should either go to disk or the maxnump should be equal to the allocated channels and equal no of drives should be free at the time of backup?

Can anyone confirm if my undertsanding is right?

Regards,
TSMDUMBER

 

[ChrisRees]

HI

Yes I think your understanding is correct.

Cheers

 

[GregE]

You're correct.

MAXNUMMP can be higher than number of allocated channels but should not be lower. If lower, you'll get a failure on however many channels you are over.

 

[hogmaster]

Hi. From experience I can say that maxnummp in some cases needs to be 1 more than channels as RMAN/Oracle asks for a new tape very quickely whne one tape is full. TSM does not "release" the full tape quickly enough to keep mountpoinst fewer than maxnummp. In a "normal" environment you will see this very rarely, and it is hard to track down.

/good luck.

 

[tsmdumber]

Thanks Guys!!