D1012/D1024 Hardware Installation and Maintenance Guide
43
Replacing an environmental services module (ESM)
In a dual-ESM configuration, ESMs are hot-swappable, which means you can replace one module without
halting I/O or powering off the enclosure. In this case, the second module takes over operation of the
storage system until you install the new module.
You may need to replace an ESM when:
•
The Fault/Service Required LED is illuminated
•
Your RAID ESM indicates a problem with the module
•
Troubleshooting indicates a problem with the module
Before you begin
Removing an ESM from an operational enclosure significantly changes air flow within the enclosure.
Openings must be populated for the enclosure to cool properly. Leave modules in the enclosure until ready
to install a replacement. For Storage Enclosures configured with a single ESM, a companion ESM blank
must be properly installed in the bottom ESM slot. Single-ESM enclosures can be upgraded to dual-ESM
status. If replacing the ESM in a single-ESM enclosure, or if replacing both ESMs in a dual-control
enclosure, use management software to record configuration settings before installing the new ESMs. See
on page 45 for instructions on installing an
additional ESM.
CAUTION:
When replacing an ESM, ensure that less than 10 seconds elapse between inserting it into a
slot and fully latching it in place. Not doing so might cause the ESM to fail. If it is not latched within 10
seconds, remove the ESM from the slot, and repeat the process.
When two ESMs are installed in the enclosure, they must be of the same model type. When replacing both
ESMs in an operational enclosure, follow these guidelines:
1.
Replace one ESM as described in these instructions.
2.
Wait 30 minutes: this pause ensures that the ESM has sufficient time to stabilize (also see
3.
Check the system status and event logs to verify that the system is stable.
4.
Replace the partner ESM as described in these instructions.
Verifying component failure
Select from the following methods to verify component failure:
•
Use management software to check the health of the system and its components.
•
Check Fault/Service Required LED (back of enclosure): Amber = Fault condition
•
Check that the CRU OK LED (back of enclosure) is off
Stopping I/O
When troubleshooting disk drive and connectivity faults, stop I/O to the affected arrays from all hosts as a
data protection precaution. As an additional data protection precaution, it is helpful to conduct regularly
scheduled backups of your data.
IMPORTANT:
Stopping I/O to an array is a host-side task, and falls outside the scope of this document.
