Preface: LOB means "large object" aka BLOB, Picture, or Text.

Reminder: there are 4 possible storage options:

1. LOB in record
2. LOB outside record, in data file
3. LOB outside data file, 4D-managed path
4. LOB outside data file, custom path

Options 3 and 4 correspond to the External Data Storage feautre that was added in 4D v13.

For option 1, 2, and 3 if the LOB is modified (including creating new records) it is journaled. If the LOB is not modified, it is not journaled.

For option 4 you need to establish your own backup and/or replication strategy to manage these resources. The LOB’s themselves will not be journaled, only the custom path that points to the LOB will be journaled. Further explanation here: https://www.youtube.com/watch?v=vVej7SwI-uM&t=40m10s