Give SNOs the ability to fully restore their node via their identity files if something breaks.
Unfortunately, there are many ways a storagenode can fail. (database malformed, hard disk fails, update not testet enough, etc.)
The SNO must then start at 0. This is particularly annoying if the storagenode is already very full and is a risk for any SNO.
It is expensive for Storj because repair traffic is generated.
The SNO is glad that if something goes wrong, not everything is lost.
Repair traffic savings: If the database fails and the SNO uses a database backup, it may be missing 1% of the data. If he now starts in recovery mode, the missing 1% of data would only need to be uploaded to the Storagenode.
If a hard disk fails and the SNO has really lost all data, there would be a lot of repair traffic. However, if the SNO buys a new hard drive within a deadline and replaces it in its server and starts its storagenode in recovery mode with its identity files and re-downloads the entire node, this would have 2 advantages:
SNO: Would not need to start from 0.
Storj: There is no need to pay for expensive repair traffic.
SNO starts in recovery mode.
Storagenode signals all satellites that it is currently in restore mode.
The database is scanned and checks whether all data is available. All files in blobs/temp/trash/garbage that are not refered in the database are deleted.
Transmission to the satellites which data is available. The satellite checks which data is missing and sends it to the storage node. Missing data is transmitted. It proceeds as if the data is sent normally to the storagenode.
After completion, the SNO is informed by e-mail and the SNO is switched off. The SNO now only needs to switch on the storage node as usual.
SNO: Happy noise