How to restore deleted/destroyed/wrongly modified data?

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What to do?

1. Write a ticket! Now! Find the ticket system here: https://tickets.cbs.mpg.de . You have to be in the institute network to do so. You might need RemoteLinux for that.
2. Tell us, which path is affected?
   • Example: I accidentally deleted the folder Important_data in /data/pt_12334/some_folder .
   • If the data in question did not reside on a file server (but e.g. on the mail server), describe it.
   • We need this information as soon as possible. Considering sending the ticket with just the path first and add more information later.
3. When was (according to your knowledge) the last time, your data was in good shape (e.g. not deleted)?
4. Describe the data's location(s) in more detail if needed.
   • Example: I accidentally deleted all the .jpg files in the second directory level in /data/pt_12334/some_folder .

The importance of the path

IT needs to know the path name first because it determines the storage block, we have to look at. We can then hit the associated red button that prevents Snapshots (backups with higher time resolution) from being removed automatically.

Snapshotting

• Enterprise backup systems are focused on snapshots. A snapshot is a consistent image taken of a storage block at a given time.
• To successful restore data, IT needs to know a point in time where the data, you're looking for still exists.
• A snapshot based backup system has a minimum granularity. For StorageUnified this is 2 hours. This means: You deleted data that was created (or copied there) less than two hours ago? There's a chance that it was never seen by a snapshot and therefore cannot be restored.
• From a user's point of view, a super-low granularity would be optimal (a second or even better: Planck time). In physical reality, granularity has to be balanced with manageability and storage requirement of the snapshots.
• Granularity of data in snapshots is being reduced over time (snapshots density per time interval becomes less and less). This is why you should write a ticket as soon as you see the need for restoring data.
• IT can disable snapshot removal for single storage blocks. This will freeze all the backup states of a storage block until your restore request is satisfied.