The following steps create a
trigger
to alert Cloudera Manager cluster administrators when free space on the Application Block
Device has fallen below a specific threshold.
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Log in to Cloudera Manager and go to the CDSW service page.
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Click Create Trigger.
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Give the trigger a name.
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Modify the Expression field to include a condition for the trigger to fire. For
example, if the trigger should fire when unallocated disk space on the Application Block
Device falls below 250GB, the expression should be:
IF (select capacity_free where mountpoint="/var/lib/cdsw" and category=FILESYSTEM and hostname="<CDSW_Master_hostname>" and LAST (capacity_free) < 250GB) DO health:concerning
On the right hand side of the page, you should see a preview of the query you have
entered and a chart that displays the result of the query as in the following sample
image. Note that if the query is incorrect or incomplete you will not see the preview on
the right.
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Click Create Trigger. If you navigate back to the CDSW service
page, you should now see the new trigger in the list of Health Tests.
For more details about Triggers, refer the following topic in the Cloudera Manager
documentation:
Triggers.