Dean wrote:
> Paul,
> 
> You certainly can create multiple st-units in one library. You *have to* 
> if you have more than one drive type in there.
> 
> But your second point won't work. You don't "bind" a drive to a st-unit. 
> You just define the *maximum* number of drives that st-unit can use. So 
> if you have a st-unit with max-drives = 15, but 20 identical drives in 
> the library, the st-unit could use *any* of those drives, up to 15 at a 
> maximum.
> 
> If your total st-unit drives is greater than the physical drives 
> available, the 20th job will just sit in the queue until one of the 
> other 19 active jobs completes, regardless of which st-unit it is going 
> to. If you have 15 drives in use in the PROD st-unit, and 4 in the DEV 
> st-unit, if the top job in the queue is a DEV job, once a drive in the 
> PROD st-unit is freed up, it will be "grabbed" for the DEV st-unit.
> 
> So giving all your PROD policies a high job priority will help achieve 
> what you want, but it won't always work.

You can bind specific drives to storage units if you really wanted to,
by only creating them with tpconfig.  If you had the need to dedicate
specific drives to storages units or decided to to purchase shared
storage option.

In our case, the robot has 10 drives and each media server has its own
storage unit for all 10 shared drives.

-- 
-------------------------------------
Dan Logcher  W91-219C ASST UNIX Admin
Massachusetts Institute of Technology
dlogcher AT mit DOT edu         617-324-5800
--Information Services & Technology--