SSKit (SnapShot Kit)

KISS tools for make snapshots in a Btrfs filesystem.

SSKit is made up of several small programs that work together, functioning as one. Currently:

• sskd: Daemon for making snapshots.
• ssmk: Makes snapshots only if necessary.
• sscl: Clean snapshots when is necessary.

Additionally, it also integrates the following tools:

• ssct: Shows Creation time and Changed time of a snapshot.
• ssst: Shows some statics of interest. (Not implemented yet)
• ssgui: Graphic user interface. (Not implemented yet)

Basic operation

On startup sskd loads /etc/sstab into memory and creates snapshots, that are stored in the specified pool directory.

Example of /etc/sstab

# subvolume    pool               frequency    quota

/              /backup/root/boot  0            30
/              /backup/root/diary 1d           30
/home          /backup/home/30m   30m          20

In every execution loop, if more time than indicated by the frequency has passed, a new snapshot of the subvolume will be created inside of its own pool, until reach the quota, and then, when quota were overpassed, it will deletes the oldest snapshot until fit to the quota.

sskd

Is the daemon. Loads /etc/sstab into memory and runs first ssmk and then sscl for each line.

ssmk

Creates a snapshot of the subvolume in the specified directory, only if the minimum frequency time is met. And only if there have been changes. The snapshot name is automatically set in the format +%Y-%m-%d_%H-%M-%S.

sscl

Delete the oldest snapshots until the quota is met.

ssct

Shows when subvolume was created and when an inode in the subvolume was last change.

ssst

Show snapshot statistics (Not implemented yet).

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TODO

• System calls.

See changelog