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flost

If you know when you lost the file, the easiest way is to use the flost command. This tool is available from any RCAC resource. If you do not have access to a compute cluster, any Gautschi user may use an SSH client to connect to gautschi.rcac.purdue.edu and run this command.

To run the tool you will need to specify the location where the lost file was with the -w argument:

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$ flost -w /your/location

Note

Only /home and /depot/ folders have backups across RCAC resources. If you know more specifically where the lost file was you may provide the full path to that directory.

Here is an example to run flost for your /home or /depot space.

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$ flost -w $HOME

This script will help you try to recover lost home or group directory contents.
NB: Scratch directories are not backed up and cannot be recovered.

Currently anchoring the search under:  $HOME
If your lost files were on a different filesystem, exit now with Ctrl-C and
rerun flost with a suitable '-w WHERE' argument (or see 'flost -h' for help).

Please enter the date that you lost your files:  2026-05-01

The closest recovery snapshot to your date of loss currently available is from
May 1, 2026 12:10am.  First, change your directory to that location:
    $ cd /home/.zfs/snapshot/zfs-auto-snap_monthly-2026-05-01-0010/username
    $ ls

Then copy files or directories from there back to where they belong:
    $ cp mylostfile $HOME
    $ cp -r mylostdirectory $HOME

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$ flost -w /depot/yourlab

This script will help you try to recover lost home or group directory contents.
NB: Scratch directories are not backed up and cannot be recovered.

Currently anchoring the search under:  /depot/yourlab
If your lost files were on a different filesystem, exit now with Ctrl-C and
rerun flost with a suitable '-w WHERE' argument (or see 'flost -h' for help).

Please enter the date that you lost your files:  2026-05-01

The closest recovery snapshot to your date of loss currently available is from
May 1, 2026 1:15am.  First, change your directory to that location:
    $ cd /depot/.snapshots/@GMT-2026.05.01-05.15.00/yourlab
    $ ls

Then copy files or directories from there back to where they belong:
    $ cp mylostfile /depot/yourlab
    $ cp -r mylostdirectory /depot/yourlab

This tool will prompt you for the date on which you lost the file or would like to recover the file from. If the tool finds an appropriate snapshot it will provide instructions on how to search for and recover the file.

flost requires a date

This tool will prompt you for the date on which you lost the file or would like to recover the file from. If the tool finds an appropriate snapshot it will provide instructions on how to search for and recover the file.

If you are not sure what date you lost the file you may try entering different dates into the flost to try to find the file or you may also manually browse the snapshots as described below.

Back to the Recovery section