IBM said a recent firmware update could cause the Seagate disk drives on more than two dozen models of its business servers to fail, leading to a situation that could cause customers to lose access to critical corporate data.

In a current support bulletin, the company said the bug affects a range of models in its BladeCenter, xSeries, and System x lines of servers.

"After a power cycle, the SATA drive is no longer available and becomes unresponsive," IBM warned. "Data may become inaccessible due to the drive not responding," according to the bulletin, which lists numerous IBM server configurations at risk from the problem.

IBM said customers should use the ServeRAID manager or other tools to determine their disk drive model and firmware.

IBM said it plans to fix the problem in a firmware update "scheduled for first quarter 2009." The company did not offer further specifics on a release date. The update, when available, will be accessible as a download from IBM's System x support Web site.

In the meantime, affected users can reduce their risk "by limiting or avoiding the number of power cycles performed," IBM said.

"This rare condition is caused by a hard drive firmware issue that allows the drive's 'event log' pointer to be set to an invalid location," IBM said. "The condition only occurs after a power cycle and not during runtime.

"Therefore, avoiding or minimizing power cycles will greatly reduce the chances of SATA drives becoming inoperable after a power cycle," the company added.

IBM said the warning applies to server products sold worldwide.