Backups

[Doug Hardie]

> On Dec 3, 2022, at 11:50 PM, Doug Hardie <bc979 at lafn.org> wrote:
> 
> I started to investigate using doveadm backup to backup my mail system.  I have a small number of users and the mail store is not large.  It uses maildir format.  I setup a test system that is not connected to the internet and started up dovecot.  I used the following command to backup one user:
> 
> doveadm backup -u ben remote:test
> 
> ben is the user is in the mail store.  Test is the actual server name.  That worked just fine.  The maildir was copied completely (as best as I can tell with ls).  Then I tried the second user:
> 
> doveadm backup -u jean remote:test
> 
> This gives 2 error messages:
> 
> doveadm(jean)[]<McRYOFI0jGN1MwAAmC+70w>: Error: Mailbox INBOX: Failed to get attribute vendor/vendor.dovecot/pvt/server/sieve/files/.dovecot: Mailbox attributes not enabled
> 
> doveadm(jean)[]<0IwxIlI0jGMgUwAAZU03Dg>: Error: Remote command returned error 65: ssh test doveadm dsync-server -ujean -U
> 
> In addition, the maildir directories are created, but there are no emails in any of them (e.g., cur).  What is the problem with the 2nd and why does it behave differently from the first?

I managed to resolve most of the issue.  I use pigeonhole on the primary server.  Apparently not having pigeonhole installed on the test machine caused the errors above.  The test machine was never intended to receive mail hence, no need to install pigeonhole as the LDA would never be used.  However, when the backup was running, it choked on transferring the sieve file.  I have no idea where the mentioned file resides as I couldn't find it anywhere on the primary server.  Installing pigeonhole resolved the issue for all but one user.  With that user, I get the following error messages:

doveadm(doug)[]<NAfSLTASjWNWTAAAmC+70w>: Panic: file istream-seekable.c: line 238 (read_from_buffer): assertion failed: (*ret_r > 0)
Abort

doveadm(doug)[]<C2AvHjASjWN2gQAAZU03Dg>: Error: read(test) failed: EOF (last sent=mail, last recv=mail_request (EOL))

doveadm(doug)[]<C2AvHjASjWN2gQAAZU03Dg>: Error: Remote command returned error 134: ssh test doveadm dsync-server -udoug -U

In addition, only a few cur files are transferred in INBOX.  Repeating the backup generates the same errors and no additional emails are transferred.  I am wondering if the problem is something in the INBOX.

-- Doug