Dell PowerVault NX3500 Administrator's Guide - Page 179

Troubleshooting Snapshots Description Cause Workaround Taking and deleting snapshots fail. Probable causes may be: • There are many client I/O requests waiting to be serviced, including a request to remove a large directory. • There are many snapshot creation/deletion requests being currently processed. • Another snapshot request for the volume is currently being executed. • The total number of snapshots reached the system limit. • For a manual request failure, retry taking or deleting the snapshot after a minute or two. • If the request originated from the snapshot scheduler, wait another cycle or two. If the failure persists, try taking or deleting the snapshot manually on the same volume. • Check the dashboard if the system is under heavy workload. If the system is under a heavy workload, wait until the workload decreases and reissue the snapshot request. • Check the snapshot schedule. A very dense snapshot schedule has a negative impact on the overall performance of the system. The accumulated snapshot rate should not exceed 20 snapshots per hour per system. • Check the total number of snapshots in the system. If the number is in the thousands, delete a few snapshots and retry. Troubleshooting 179