TSM configuration question

[liyboviz]

Hi,



I started to admisitrate our University TSM server and its 140 client nodes.



when I took over the TSM system I got the clients devided into 2 groups (one for our computation center servers, 30 clients, and the other for outside servers), with a 6 and a 4 gb disks as their disk storage pools and 2 pools on our single tape library as their tape pools.



my question : is there a benefit from dividing the 10 gb and tapes into 2 groups execpt for logical seperation of things?



thanks,Assaf

 

[chad_small]

The benefits are in scheduling needs, option sets, and administration. When you seperate Domains you will find it easier for you to delegate authority. If there is someone you want to admin some of the clients and not others you can make them a domain admin over those clients, option sets can be created that fit specific client types (although a client option set is not domain specific it makes it easier to manage them), and schedules can be created and associated to clients based on their domain rather then selectively choosing those clients from a single domain.

 

[liyboviz]

hi chad,



sorry, but that wasn't my question... I asked about the storage, I know about the benefits of using domains but my question related to benefits from backing up to a single big disk or to 2 smaller ones.



thanks, Assaf

 

[robbenleaf]

Splitting up the tape pools can significantly reduce restore times for nodes in non-collocated policy domains.



If you have data from 30 nodes on, say, 100 tapes, there will likely be fewer tape mounts when trying to restore a lot of data to a single node than there would be if those nodes were sharing a larger pool (say, 200 tapes) with another 30 nodes. Increased tape mounts can dramatically increase restore times.



This can be a major consideration if your TSM solution is part of a comprehensive disaster recovery plan - i.e., how long will it take to get the 15 (or however many) most important nodes back on-line in the case of a disaster?



There may be a point at which adding more nodes and tapes to a tape pool no longer affects full-restore times; I'm sure trying to figure out where that point is would be very difficult, and would involve a lot of variables (number of files per node, backup schedules and volatility of data, expiration and tape reclamation policies, etc.).



-Robben