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Example of what happens when Snapshot copies exceed the reserve

Because there is no way to prevent Snapshot copies from consuming disk space greater than the amount reserved for them, it is important to reserve enough disk space for Snapshot copies so that the active file system always has space available to create new files or modify existing ones.

Consider what happens in the following example if all files in the active file system are deleted. Before the deletion, the node run -node nodename df output is as follows:
Filesystem          kbytes  used    avail  capacity
/vol/vol0/          3000000 3000000 0       100%
/vol/vol0/.snapshot 1000000 500000  500000   50%
After the deletion, the node run -node nodename df command generates the following output:
Filesystem          kbytes  used    avail  capacity
/vol/vol0/          3000000 2500000 500000   83%
/vol/vol0/.snapshot 1000000 3500000 0       350%

The output shows that the entire 3,000,000 KB (3 GB) in the active file system is still being used by Snapshot copies in addition to the 500,000 KB (0.5 GB) that was used by Snapshot copies before the deletion. Therefore, a total of 3,500,000 KB (3.5 GB) is being used by Snapshot copy data, which is 2,500,000 KB (2.5 GB) more than the space reserved for Snapshot copies. This means that 2.5 GB of space that would be available to the active file system is now unavailable to it. The post-deletion output of the node run -node nodename df command lists this unavailable space as used even though no files are stored in the active file system.