Filesystem Backups in the CS Department | UMD Department of Computer Science Technical FAQ

1 Retention Policy for Junkfood Home Directories and Web Directories
2 Recovering Files

Retention Policy for Junkfood Home Directories and Web Directories

          An hourly copy is kept for 5 days.
A daily copy is kept for 2 weeks.
A weekly copy is kept for 2 months.
A monthly copy is kept for 2 years.

Recovering Files

If you need to restore a file from your Junkfood Home Directory or your Web Directory (www.cs.umd.edu/~user), follow the simple steps below.

To restore a file from “junkfood home”:

Log in to a junkfood system.
Go to the backup directory: cd /fs/userdata/.zfs/snapshot
Directories are listed there by on backup date and time and then by user. Go to, for example: cd 2013-01-28-170000/$USER/
Copy the desired file back to the desired junkfood home directory:

cp deletedFile ~/folderName

To restore a file from www.cs.umd.edu/~userName:

Log in to a junkfood system.
cd /fs/wwwusers/.zfs/snapshot
Directories are listed there by on backup date and time and then by user. Go to, for example: cd 2013-01-28-170000/$USER/
Copy the desired file back to your web directory:

cp deletedFile /fs/wwwusers/$USER/folderName

Please note that /tmp directories on the junkfood machines are not backed up. Any data that was written there will not be retrievable when the /tmp is cleared by a system reboot.

If you are unable to find the desired file or you would like to restore a file from a system not mentioned here, please contact IT staff by completing this form.

To restore a file from www.cs.umd.edu/class/cmscXXX:

Log in to a junkfood system.
cd /fs/www/.zfs/snapshot
Directories are listed there by on backup date and time and then by user. Go to, for example: cd 2025-01-01-170000/class/cmscXXX
Copy the desired file back to a directory:

cp deletedFile /tmp