Backuppc v4, rsync_bpc

Ubuntu 21.10

Upon upgrade backuppc failed.
I upgraded rsync_bpc 3.1.3.0 as requested by backuppc, the backuppc server starts (before did not) and run OK but backups fails with this code error:

Got fatal error during xfer (rsync error: unexplained error (code 255) at io.c(226) [Receiver=3.1.3.0])
2021-10-26 15:02:57 Backup aborted (rsync error: unexplained error (code 255) at io.c(226) [Receiver=3.1.3.0])

If I rsync server to remote there are no errors.

I know not many people use backuppc so I have no expectations someone to give a piece of advice but maybe somebody will have the same issue.

I have now installed:

root@zika:/home/brad# rsync_bpc --version
rsync_bpc  version 3.1.3.0  protocol version 31
Copyright (C) 1996-2018 by Andrew Tridgell, Wayne Davison, and others.
Web site: http://rsync.samba.org/
Capabilities:
    64-bit files, 64-bit inums, 64-bit timestamps, 64-bit long ints,
    socketpairs, hardlinks, symlinks, IPv6, batchfiles, inplace,
    append, ACLs, xattrs, iconv, symtimes, no prealloc

rsync comes with ABSOLUTELY NO WARRANTY.  This is free software, and you
are welcome to redistribute it under certain conditions.  See the GNU
General Public Licence for details.

and:

root@zika:/home/brad# rsync --version
    rsync  version 3.2.3  protocol version 31
    Copyright (C) 1996-2020 by Andrew Tridgell, Wayne Davison, and others.
    Web site: https://rsync.samba.org/
    Capabilities:
        64-bit files, 64-bit inums, 64-bit timestamps, 64-bit long ints,
        socketpairs, hardlinks, hardlink-specials, symlinks, IPv6, atimes,
        batchfiles, inplace, append, ACLs, xattrs, optional protect-args, iconv,
        symtimes, prealloc, stop-at, no crtimes
    Optimizations:
        SIMD, no asm, openssl-crypto
    Checksum list:
        xxh128 xxh3 xxh64 (xxhash) md5 md4 none
    Compress list:
        zstd lz4 zlibx zlib none
    
    rsync comes with ABSOLUTELY NO WARRANTY.  This is free software, and you
    are welcome to redistribute it under certain conditions.  See the GNU
    General Public Licence for details.

Thanks a lot!

Update: I solved this issue (dependency).

I did run into the same issue, an found this page. After a lot of Googeling I found a solution that worked for me.

If you look into XferLOG of the backup run that failed, you can see the command that BackupPC tried to run. (I found the XferLOG on the summary page of the host). I had multiple errors when I tried to run the command on the BackupPC server as the BackupPC user.

I had added a --verbose option to the RsyncSshArgs, that was unknown to rsync_pbc. The error from this command I only noticed when trying to run the command manually.

I also wanted the backup to log in to this client as a different user than backuppc, in this case the root user. (Yes I know.... I should use another user...) But because of this I also had the argument "-l root", which also was unknown to rsync_pbc.

I could not find a good solution to change the user in the BackupPC, so I added the information needed to ~backuppc/.ssh/config, so the default user for this client now was root.

Host clientmachine
  User root

More information about the .ssh/config file you can find in the man pages.

Now it worked for me!

Yes, it's a work-a-round, but if it works... and so forth...