First check how much space used or consumed by DiskGroup2. Also you need to check how much space is free for DiskGroup1 because when you delete DiskGroup2 then all data will migrate from DiskGroup2 to DiskGroup1. This process is called VDG drain. So execute command "show disk-groups" to check how much shows as "Size" which is nothing but total size of the VDG and also see "Free" which is nothing but shows how much space free in that VDG. From that you can calculate how much is used or consumed.
Also keep in mind, for optimal performance:
All virtual disk groups (VDGs) in the same tier should have the same RAID level, capacity disks, and physical number of disks.
Hope this helps!
Regards
Subhajit
I am an HPE employee
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