Decision making logic of which Secondary storage to be used #3041
Description
Related to this unresolved issue https://issues.apache.org/jira/browse/CLOUDSTACK-2919
Add proper check for disk space on secondary storage to be used for volume migration across clusters. The current logic does not validate if volume will fit in the destination storage pool, but only checks if whether secondary storage disk utilization has not reached 90%.
ISSUE TYPE
- Improvement Request
- Enhancement Request
COMPONENT NAME
Storage
CLOUDSTACK VERSION
4.9+
CONFIGURATION
2+ Secondary Storage (ImageStore) pools with Zone scope
2+ Clusters
OS / ENVIRONMENT
N/A
SUMMARY
When performing cross-cluster volume migration in multi ImageStore environments within the same Zone. The volume is first copied the secondary storage, attached to a worker VM and then migrated to the destination storage pool. This is procedure is only successful when the following 2 conditions are satisfied
- The ImageStore disk usage should not exceed a hardcoded value of 0.9 (90 %)
- The size of the volume the volume to be migrated should exist the amount of free space available in the ImageStore.
STEPS TO REPRODUCE
- Fill up secondary storage disk up to 90%
- Perform cross-cluster volume migration through UI or API
EXPECTED RESULTS
An exception should be thrown explaining that no suitable secondary storage pool was found for volume migration.
ACTUAL RESULTS
CloudStack selects a random secondary storage pool and attempts to migrate the volume anyways and fails when the size of the volume exceeds the amount of free space within that particular secondary storage.