Hardware manual

Group Administration Group monitoring
15–25
Monitoring volumes and snapshots
Make sure volumes and snapshots are online or offline. Make sure that thin-provision volumes are not about to run
out of volume reserve. Also check free volume space.
To display information for all group volumes, click
Volumes in the lower-left panel and then click Volumes in the
far-left panel. The Volume Summary window appears.
To display detailed information about a specific volume, expand
Volumes and select the volume name. The
Volume Status window appears. To display snapshot information, expand a volume name and select a snapshot
timestamp. The Snapshot Status window appears.
Monitor volume and snapshot space as follows:
• For volumes that are not thin-provisione
d
, check for in-use space that is near a volume’s reported size. When
free volume space is exhausted, writes to the volume fail, potentially disrupting applications, but the volume
remains online.
To increase free volume space, increase the reported volume size. See Increasing the reported size of a volume
on page 10-5.
• For thin-provisioned volumes, check for in-use
space that is near the maximum in-use space setting.
Thin-provisioned volumes are set offline if their maximum in-use spa
ce is set to less than 100% and a write
exceeds this value. If the maximum in-use space is set to 100%, and a write exceeds this value, the write fails,
but the volume remains online.
To increase free volume space, increase the reported volume size. See Increasing the reported size of a volume
on page 10-5. You can also increase free volume space by increa
sing the value of the
maximum in-use space
value up to 100%.
• Check the snapshot reserve free space and the space recovery setting. If free snapshot rese
rve is exceeded, the
space recovery setting controls whether the oldest snapshots are deleted to free space for new snapshots, or the
volume and its snapshots are set offline.
To increase the snapshot reserve or change the space recovery setting,
see About snapshot reserve settings on
page 11-2.
Each volume and snapshot has two status values:
• Requested status – Administrator-applied setting for the volume or
s
napshot. For example, an administrator
can set a volume online or offline. See Table 15-23.
• Current status – Actual status of the volume or snapshot, regardles
s of the requested status. See Table 15-24.
Under normal conditions, the requested status and current status are the same.
However, an event in the group can
result in a current status that differs from the requested status.
For example, if an administrator sets a volume on
line, but a member containing volume data is shut down, the
requested status is
online, but the current status is offline-member-down. Always investigate when the
current status is different from the requested status.
The group sets a volume or snapshot offline if network problems oc
cur or if a member that contains volume data is
not available. If the group sets a volume offline because of a problem, the group also sets all its snapshots offline.