rsync_bpc: write failed on "[…]": File too large (27)

[xtaran]

Hi,

we got the following error when trying to backup a file which has 2.049 GiB size, i.e. slightly over 2 GiB:

Running: /usr/libexec/backuppc-rsync/rsync_bpc --bpc-top-dir /var/lib/backuppc --bpc-host-name […] --bpc-share-name /home --bpc-bkup-num 520 --bpc-bkup-comp 3 --bpc-bkup-prevnum 519 --bpc-bkup-prevcomp 3 --bpc-bkup-inode0 1270854 --bpc-log-level 1 --bpc-attrib-new -e /usr/bin/ssh\ -l\ root --rsync-path=/usr/bin/rsync --super --recursive --protect-args --numeric-ids --perms --owner --group -D --times --links --hard-links --delete --delete-excluded --one-file-system --partial --log-format=log:\ %o\ %i\ %B\ %8U,%8G\ %9l\ %f%L --stats --checksum --timeout=72000 vcc-prd-01:/home/ /
full backup started for directory /home
Xfer PIDs are now 26685
This is the rsync child about to exec /usr/libexec/backuppc-rsync/rsync_bpc
Xfer PIDs are now 26685,26687
xferPids 26685,26687
    same   recv >fc........ rw-r--r--      841,     600         0 […]
rsync_bpc: write failed on "[…]": File too large (27)
Done: 0 errors, 1 filesExist, 1342177280 sizeExist, 1341849014 sizeExistComp, 0 filesTotal, 0 sizeTotal, 0 filesNew, 0 sizeNew, 0 sizeNewComp, 1270855 inode
rsync error: error in file IO (code 11) at receiver.c(449) [receiver=3.1.3.0]
    same   recv >fcst...... rw-r--r--        0,       0 2200378428 […]
DoneGen: 0 errors, 0 filesExist, 0 sizeExist, 0 sizeExistComp, 457 filesTotal, 9774730 sizeTotal, 0 filesNew, 0 sizeNew, 0 sizeNewComp, 1270864 inode
rsync_bpc exited with fatal status 11 (2816) (rsync error: error in file IO (code 11) at receiver.c(449) [receiver=3.1.3.0])
Xfer PIDs are now 
Got fatal error during xfer (rsync error: error in file IO (code 11) at receiver.c(449) [receiver=3.1.3.0])
Backup aborted (rsync error: error in file IO (code 11) at receiver.c(449) [receiver=3.1.3.0])

This issue is usually only present in file system related limitations. But since rsync_bpc (as I understand) doesn't write to any real file system, this is probably related to the BackupPC-specific backend.

In any case, the file system of /var/lib/backuppc/ in this case is XFS:

# xfs_info /dev/mapper/datavg0-bkpc
meta-data=/dev/mapper/datavg0-bkpc isize=512    agcount=274, agsize=8388608 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1    bigtime=0
data     =                       bsize=4096   blocks=2290676736, imaxpct=5
         =                       sunit=64     swidth=64 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=131072, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
# df -hT /var/lib/backuppc/
Filesystem               Type  Size  Used Avail Use% Mounted on
/dev/mapper/datavg0-bkpc xfs   8.6T  6.5T  2.2T  76% /var/lib/backuppc

Both, the BackupPC server as well as the to be backed up host are running on Debian GNU/Linux 11 Bullseye, amd64 (x86_64) architecture.

Some more information on the used version:

# /usr/libexec/backuppc-rsync/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.