TSM 5.4 offers a workaround to the core problem of the product, which is that recovery times for a full restore are very slow. TSM uses a method called "incrementals forever," which means that the product makes one full backup and then every subsequent backup, saving only the changes to the data, thereby reducing the backup window. The downside to this approach is that files are spread out all over the place resulting in poor utilization and slow restore times. Full backups, by contrast, put all the data together making it easier to recover.
Adam Richardson, data recovery architect with EPIQ Systems Inc., depends on TSM to manage over 250 terabytes (TB) of backup data consisting of nearly 2 billion files. The firm's nightly incremental backups total 3.5 TB per night.
"This new feature would allow most restores to come directly from disk while keeping all of the historical versions on tape," he said in an email to SearchStorage.com. He added that businesses relying on TSM for disaster recovery could reduce their recovery times by replicating their active data to the hot site.
Another TSM user, who preferred to remain anonymous as he does not have permission to speak on behalf of his company, said that the improvements in TSM 5.4 have come too late for his firm. He stores 266 TB on TSM 5.3 but was forced to buy a virtual tape library (VTL) from EMC Corp. to improve restore times. "It's been a lot easier to perform restores this way," he said. TSM 5.3 was released in December 2004.
An industry expert familiar with how TSM works described the "active storage pool" enhancement as "lipstick on a pig." Preferring to remain anonymous, he said, "You can restore the most recent data, but how helpful is it to people restoring data from two months ago?"
Key management improvements
TSM 5.4 server will now perform centralized key management for the administrator rather than this being a manual task. This was a fix pack but is now integrated into the product. In addition, a data shredding feature allows users to designate a pool as "shreddable," prompting TSM to write a random pattern over that data ensuring it is erased.
On the hardware front, TSM now supports application managed encryption with the ability to generate and communicate encryption keys to the IBM TS1120 drives, which perform encryption at the drive level. This capability improves performance by allowing encryption on the tape drive, alleviating the resource intensive encryption processing at the data source.
Integration with NSeries NAS boxes
Through NDMP, IBM has tightened up integration with its NSeries network attached storage (NAS) devices, to take advantage of the storage management hierarchy features in TSM. The NSeries boxes can now be included in disaster recovery plans, such as offsite vaulting, if required.
Other improvements in TSM 5.4 include the ability to more easily upgrade from TSM Express to TSM Enterprise and a change in the license structure to bring TSM in line with the rest of IBM's software products. IBM officials said this would not mean a pricing change for users.