H205201: Environmental Service Module (ESM) will reboot after 994 days of continuous up-time - IBM DS4000 EXP100, DS4000 EXP700, DS4000 EXP710


RETAIN tip: H205201


After 994 days of continuous up-time, an Environmental Service Module (ESM) will reboot. Depending on the specifics of your configuration, there is a very slight chance that two ESMs could reboot at the same time causing a temporary loss of access to your data.

Affected configurations

The system is configured with one or more of the following IBM Options:

  • EXP100 SATA Storage Expansion Unit (1710-10U), any model
  • EXP700 Expansion Unit, type 1740, any model
  • EXP710 Storage Enclosure (1740-710), any model

This tip is not system specific.

This tip is not software specific.


Plan a maintenance window to reboot the ESMs before they reach 994 days of continuous up-time. This can be performed in a few different ways. Here are two examples:

  • Reload the same version of ESM firmware, as this will systematically reboot each ESM in the configuration. In general, this procedure is a concurrent operation. However, refer to the Readme file in the ESM/Hard Disk Drive (HDD) 1.77 or later package for any restrictions related to this operation.
  • Power Cycle the entire configuration, making sure to follow proper order of powering down and powering up.

Additional information

Due to a hardware limitation in the up-time counter of the affected storage enclosures, the ESMs must reboot after 994 days of up-time. There is no fix for this issue.

Unfortunately, there is no reliable technical method to determine exactly how long it has been since the last time the ESMs rebooted.

Applicable countries and regions


Document id:  MIGR-5089599
Last modified:  2012-04-26
Copyright © 2014 IBM Corporation