HP MSA 2040 Troubleshooting Manual page 24

If a power cycle is needed, follow these steps:
1. Shut down, dismount, or unmap the hosts (servers) with access to the MSA volumes. This
allows any pending writes in Application cache or Server memory to flush to the MSA
controllers write-back cache.
2. Shut down both array controllers in a dual controller system or a single controller system by
using SMU or CLI interface. This allows the controllers to flush the controller write cache to
the disks.
NOTE:
without properly shutting down the array controllers first. Shutting down the controllers allows
for any write cache in the controller modules to be properly flushed down to the Hard Drives.
Removing power from single JBODs may adversely affect Vdisk or disk groups that are
shared between enclosures.
3. JBOD Enclosures only need to be powered off for routine maintenance. The JBODs must
be powered off only after the controllers are properly shut down using the CLI or SMU. To
power off the JBOD enclosures either remove the power cables or turn off the switch,
whichever step is applicable for your power supplies.
Perform the reverse steps when restoring power to the Storage infrastructure. Power on the
JBOD enclosures from the bottom to the top, allowing for the drives in each JBOD to power up
before powering the next JBOD enclosure. If the enclosures are powered off, wait a minimum of
one minute after powering on the last JBOD enclosure before powering up the MSA controllers.
This allows the Hard Drives enough time to spin up before the array controllers come online.
CAUTION:
power from a controller processing host IO could have negative consequences to data integrity.
NOTE: Power on the JBOD enclosures from the bottom enclosure to the top, allowing enough
time for the drives to spin up. The 6TB and 8TB drives take time.
24 Troubleshooting HPE MSA 1040/2040 Storage
Never remove the power cords from the Power Supplies on the RAID enclosure
Never power cycle an array without knowing the status of the controllers. Removing