IBM has upgraded Tivoli Storage Manager (TSM), its legacy
backup application used by about 20,000
companies, to make it easier and faster to restore the most
recently backed-up files.
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.
"We can now group all active data in one place with a feature
called active storage pools," said John Connor, marketing manager
for TSM. Version 5.4 of the software makes two copies of the data,
one that goes to primary disk and a second that sits in cache to
keep it available for recovery. Active data is always the most
recently backed-up data. If there were 100 files in an active and
primary pool with a 10% change rate to those files, the oldest 10
files in the active and primary pools would become inactive,
replaced by the newer files.
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.