Administrator Guide

Table Of Contents
Limitations with storage-volume expansion
The following limitations apply to the storage volume expansion method:
For virtual volumes built on RAID 1 or distributed RAID 1 devices, a maximum of 1000 initialization processes can run
concurrently per cluster. If this limit is reached on a cluster, then no new expansions can be started on virtual volumes with
these geometries until some of the previously started initialization processes finish on that cluster.
Virtual volumes that do not contain RAID 1 or distributed RAID 1 devices are not affected by this limitation.
Troubleshooting and health indications
When a volume expansion fails, information as to why it failed is added to the health indications attribute. When an
expansion fails it does not degrade overall health, operational status, or service status of a virtual volume.
The metro node Troubleshooting section of the SolVe Desktop contains procedures for recovering from an error with volume
expansions.
Rediscover the array
You may need to rediscover the array after expansion. Depending on the type and configuration of the back-end array, the
storage array might not support auto-discovery by metro node.
Best practice
If metro node does not automatically detect the change in the storage volume, use the array-rediscover command to
force metro node to recognize the back-end expansion.
If you are performing multiple storage volume expansions on the array, complete all storage volume expansions, and rediscover
the array only once to force metro node to detect all the expansions.
Some arrays need specific system settings to enable support of auto discovery.
Refer to the SolVe Desktop for the procedures to configure storage arrays for metro node.
NOTE:
Review the applicable best practices for host and array connectivity and configuration in the SolVe Desktop. Some
arrays require specific settings for automatic detection.
CAUTION: Array rediscoveries may consume excessive resources and can be disruptive to I/O. Rediscover arrays
only when necessary.
40 Volume expansion