Partitioning tape library between two NBU domains (from 6.5 to 7.5)
HI I wondered if anyone could give me some tips on my thoughts around the following:
I have a NBU 6.5 environment with two IBM3584 tape libraries. Most servers backup up to disk at night, then this is off to tape during the day.
I also have a NBU 7.5 environment which has 2 NBU 5220s, with a master server. This is where I need to get to from the 6.5 envirnoment.
I am in a position where I *might* run into disk space issues on these appliances due to the amount of large oracle databases that have yet to be migrated over (my understanding is that the rate of de-dup is not as high on this data). It's a catch 22 as I won't know how it will go until I actually get these backups over onto the 7.5 environment. There is of course the possibility that the amount of disk I have available will actually be more than adequate.......
So I thought I would like to be able to partition my tape library to allow use by BOTH nbumaster servers (the 6.5 and the 7.5) - can anyone tell me if this is achievable, and worthwhile? Even if one drive were available to the new environment, this might help in the long run?
Else, I may have to opt to lower the data retention on the backup policies until I can have all of the backups over onto the 7.5 appliances, and THEN move the tape libraries over for use in this environment.
Has anyone else had to think about this, or an alternate solution?
Many Thanks
The IBM 3584 series can be partitioned. It requires a license from IBM I believe.
It is partioned by turning on ALMS (advanced library management system), you then create 'logical librarys' and to these you assign tape drives, and slots. If I recall correctly, you then assign barcode ranges to the tapes, so eg.
AA0000L4 > AA1000L4 goto partition 1
AA1001L4 > AA2000L4 goto partition 2 etc
Persoanlly I would advise spliting the tapes up by a letter, not number.
AAxxx > library parttion1
ABxxx > partition 2
ACccc > partition 3
You also have to assign one of the drives that is in each partioition as a 'control path' - this allows the library to present 'two' robots to the operating system of the robot control host(s).
Be aware that turning on ALMS enables the virtual I/O (virtual CAP / MAP) which is a great feature. However, there is a certain setting which I will have to look up tomorrow (can't remember ) which causes issues with NetBackup using the CAP if it is set wrong (there is a technote available).
... and that, in a nutshell is how to set up a partitioned 3584 (hopefully I dodn;t forget anything). The IBM manuals show the steps, just have to read through a couple of times,
Fom the NBU side, if you are using Solaris as the robot control host there is (at least in my experience) a massive catch you out when configureing the sg driver. sg.build doesn't automatically detect the robot and place an entry in the sg.links and sg.conf files - so after an sg driver rebuild, you'll be missing at least one of the robots (the other will still be available depending on how you rebuild the driver). It's easily fixed, the robot will have the same WWN as the drive that it uses as the control path, but one lun 'down' - you just duplicate the line containing this WWN in the sg.links and sg.conf files in /usr/openv/volmgr/bin/drivers but increase the lun for these new entries by 1. Then run the device wizard to reconfig, and then run an inventory.
