How long does check -chunks take?

Following the suggestion in the latest release notes I’m checking the chunks on my sftp server.

I started the check command 24 hours ago. duplicacy checked that all chunks existed successfully, then stated Verifying 421147 chunks and has been sitting there like that.

duplicacy check -all -chunks -threads 4    
<snip>
All chunks referenced by snapshot userland at revision 67 exist
Verifying 421147 chunks

I’m running the cli on the server itself. (Its no speed demon, 1.5ghz dual core AMD Turion II.)
Just wondering if anyone knows how long it will take.

I can still see duplicacy process in htop and they.re sucking up most of the cpu, so it seems its running ok.

Apparently the answer is 1 day 3 hours.

At least one chunk has a problem - is this an expected result of check?

Failed to decrypt the chunk 0280e56d315e1996687b000535b69ee0edbd2339d57fe9a21f70d3a21e423726: cipher: message authentication failed; retrying
Failed to decrypt the chunk 0280e56d315e1996687b000535b69ee0edbd2339d57fe9a21f70d3a21e423726: cipher: message authentication failed; retrying
Failed to decrypt the chunk 0280e56d315e1996687b000535b69ee0edbd2339d57fe9a21f70d3a21e423726: cipher: message authentication failed; retrying
Failed to decrypt the chunk 0280e56d315e1996687b000535b69ee0edbd2339d57fe9a21f70d3a21e423726: cipher: message authentication failed

-check gives up as soon as it finds one invalid chunk. So it took 1d 3h to find the invalid chunk; there might be additional invalid chunks, as not all of them were checked… So checking all your chunks might take longer than that.

As to how to fix, you can read about my adventures with an invalid sftp backup here : Invalid chunks in 1/4 snapshots
There’s a few pointers in there.

Not being able to easily identify all invalid chunks, and which revisions they are used in, is a major pain I’d say… I myself checked each revision one by one, and when an invalid chunk was found, I removed that file, and the revision in question, then continued to check other revisions, continuing to delete chunks and revisions until I went through all of them. I then made sure a new revision was created, I checked it, and double-checked it by doing a full restore (on the server). When I was sure all of those were OK, I ran a prune -exhaustive to deleted the now-unused chunks (those only used in snapshots I manually deleted).

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Thanks @GuillaumeBoudreau

-check gives up as soon as it finds one invalid chunk.

Thats very good to know!
I will continue to investigate and fix.

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