Snapshot overhead when moving files inside SnapshotIQ policy directory

Question

Hi

If I have /ifs/MyDir with a SnapshotIQ policy, and if I move data from /ifs/MyDir/SubDir-A to /ifs/MyDir/SubDir-B, will this affect filesystem space consumption for as long as snapshots exist with said data "still present" in /ifs/MyDir/SubDir-A?

Copy the data to destination would not be "visible" to SnapshotIQ and affect filesystem space consumption. But what about data move?

What about CLI rename?

Does anybody have knowledge or experience on this?

Thanks in advance!

tenortim · Accepted Answer

Hi @CendresMetaux ,

if you rename a directory within a snapshot (`mv SubDir-A SubDir-B`, then that won't cause any changes to the data. The snapshot will grow by a very small amount as it will retain the changed blocks in the directory itself because of the change in name,

If you leave both directories intact and move files between them, again, the underlying file isn't changing and only the blocks that change in the source directory because files are being removed from that directory will change.

In both of the above cases, the rename only changes the metadata. The older snapshots in SubDir-A will be pointing to the inodes (LINs) of the moved files, and those inodes and files still exist. If you then deleted or changed those files in SubDir-B, then the affected blocks from the files would be moved into the current snapshot.

Does that answer your question?t

Tim

DELL-Sam L · Answer

Hello CendresMetaux, Here is a link to a kb that maybe of assistance. https://dell.to/3vaQQVb

CendresMetaux · Answer

Thanks Tim, thats about what I was looking for

Isilon

Snapshot overhead when moving files inside SnapshotIQ policy directory

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