What types of FDB backups are point-in-time restorable?

Using FoundationDB Running FoundationDB
1

I’ve been poring over the FoundationDB backup/restore documentation, and I have a few questions.

Are all of my assumptions here correct?

  1. When performing a continuous backup, the mutation log contains all mutations since the start of the backup. When a snapshot occurs, the mutation log is not truncated to the start of that snapshot.
  2. FDB is roughly “point-in-time” restorable to any point in time when the continuous backup was running and a mutation log is present, since the mutation log will contain all key versions, even of deleted/cleared keys.
  3. When a key is cleared, a tombstone is generated, but the version is eventually deleted from the storage server.
  4. DR backups have the same behavior regarding deleted keys, additional versions of data are not maintained.
  5. Therefore, the only way to maintain a “point-in-time” backup is to keep a continuous backup running.
2
  1. Correct. Taking a snapshot does not affect the mutation log stored somewhere.
  2. Correct.
  3. Correct. But see p 2.
  4. What do you mean as “Additional versions of data”? If you clear a key from the main primary database, the same key will be cleared from the DR database after a short timelag.
  5. Correct.
3

Thanks for these answers.

Regarding point 4: By “additional versions of data” I’m referring to the “commit version” described in the FDB docs here.

I think your answer here answers my question on point 4: