rsync error during backup or recover

[dblugeon]

Hello enterpriseDB Team,

On a fresh server (rocky linux 9.3), I install barman 3.9 (from pgdg repo). When I backup a postgresql 13 server (rocky linux 9.3 too), I have these warning and error: 2024-01-10 15:40:30,584 [24439] barman.copy_controller INFO: Detected rsync version less than 3.1. top using '--ignore-missing-args' argument. 2024-01-10 15:40:30,592 [24439] RsyncPgData WARNING: Overflow in read_varint() 2024-01-10 15:40:30,592 [24439] RsyncPgData WARNING: rsync error: error in rsync protocol data stream (code 12) at io.c(1754) [sender=3.2.3] 2024-01-10 15:40:30,592 [24439] RsyncPgData WARNING: rsync error: received SIGUSR1 (code 19) at main.c(1599) [Receiver=3.2.3] 2024-01-10 15:40:30,692 [24439] barman.copy_controller ERROR: Unable to retrieve reference directory file list. Using only source file information to decide which files need to be copied with checksums enabled: {'ret': 12, 'out': '', 'err': 'Overflow in read_varint()\nrsync error: error in rsync protocol data stream (code 12) at io.c(1754) [sender=3.2.3]\nrsync error: received SIGUSR1 (code 19) at main.c(1599) [Receiver=3.2.3]\n'} 2024-01-10 15:40:30,918 [24439] barman.copy_controller INFO: Copy step 2 of 13: [global] create destination directories and delete unknown files for remote tablespace directory 'db_toto_data': /home/san1/pg_tbs/toto/toto_data/ 2024-01-10 15:40:31,143 [24439] barman.copy_controller INFO: Copy step 3 of 13: [global] analyze remote tablespace directory 'db_toto_index': /home/san1/pg_tbs/toto/toto_index/ 2024-01-10 15:40:31,149 [24439] RsyncPgData WARNING: Overflow in read_varint() 2024-01-10 15:40:31,149 [24439] RsyncPgData WARNING: rsync error: error in rsync protocol data stream (code 12) at io.c(1754) [sender=3.2.3] 2024-01-10 15:40:31,149 [24439] RsyncPgData WARNING: rsync error: received SIGUSR1 (code 19) at main.c(1599) [Receiver=3.2.3] 2024-01-10 15:40:31,250 [24439] barman.copy_controller ERROR: Unable to retrieve reference directory file list. Using only source file information to decide which files need to be copied with checksums enabled: {'ret': 12, 'out': '', 'err': 'Overflow in read_varint()\nrsync error: error in rsync protocol data stream (code 12) at io.c(1754) [sender=3.2.3]\nrsync error: received SIGUSR1 (code 19) at main.c(1599) [Receiver=3.2.3]\n'} I don't understand 3 points:

1. why barman detects rsync < 3.1 when rocky linux ships rsync 3.2.3 ?
2. warnings about rsync error
3. the barman error about directory file list and his impact for backup or recovery.

I also check that I can backup or recover without error (exit code 0). Despite these errors, I was able to restore a physical backup and make pg_dump then pg_restore without problem.

os version: rocky linux 9.3 barman version: 3.9.0-1PGDG.rhel9 rsync (from rocky) version: 3.2.3 python version: 3.9.18

Regards

[gcalacoci]

Hi, Could you run the barman diagnose and post the output here, after removing any sensitive information from the output?

about your question number 3. is this the first backup?

[dblugeon]

ello @gcalacoci, Thank you for your response. Here the diagnose result on a barman server on rocky 9.3: diagnose_rocky8.json

about your question number 3. is this the first backup? It was the first backup, but I have same log lines with following backups.

I make an another test : install barman 3.9 on a rocky linux 8 which makes backup of postgresql instance under rocky linux 8 too, I don't have any warning/errors about rsync. I uploaded the diagnose result for this test : diagnose_rocky9.json

Regards

[dblugeon]

Hello, I make another tests and actually, I can't reproduce the problem. I isolate that my first postgresql vm has only affected by this problem. I schedule another test the next week, depending his result, I will close this issue.

Regards

[dblugeon]

Hello @gcalacoci, I found what is the problem. It wasn't a problem from barman but from rsync.

Rocky/RHEL/xxx 9 has rsync in 3.2.3 version and this version is affected by WayneD/rsync#84.

You can have theses warnings if:

• You use rsync method
• You use dns name to connect your pg server and tis name contains the 'V' character

To fix these warning:

• do not use uppercase in ssh comand in /etc/barman.d/PG_VM.conf
• upgrade to rsync 3.2.4+
• use vm's ip address

I check the debug log during a backup. Barman use this options in this first attempt

rsync .... -e "ssh 'postgres@PG_VM.acme' '-o' 'BatchMode=yes' '"... --ignore-missing-args --itemize-changes --itemize-changes --no-human-readable --list-only -r /path/PG_VM/base/20240115T103614/16404/ It's failed with rsync 3.2.3 and barman fail back with rsync .... -e "ssh 'postgres@PG_VM.acme' '-o' 'BatchMode=yes' '"... --itemize-changes --itemize-changes --no-human-readable --list-only -r /path/PG_VM/base/20240115T103614/16404/ then in the last attempt rsync ... --itemize-changes --itemize-changes --no-human-readable --list-only -r :/path/PG_VM/base/20240115T103614/16404/

So these warnings are not real problem, thanks to these barman's fall-back.

Thank you for your time and sorry for the disturbance.