backup_and_restore.sh: should "catch" tar error code 1

[ralfbergs]

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Description

In one week of doing mailcow backups using /opt/mailcow-dockerized/helper-scripts/backup_and_restore.sh, I already got once the below error:

/etc/cron.daily/mailcow-backup:
/bin/tar: /rspamd: file changed as we read it

This message was output because the tar return code was not 0, but 1.

I would argue that when backing up a running system, file changed as we read it is to be expected. So I would propose to change the backup script to ignore an RC of 1, but only report on >1. (According to the tar man page there is only 2, which means "fatal error.")

Steps to reproduce:

1. Set up daily backups using the standard mailcow backup script.
2. Observe this for a while.
3. After a couple of days, you will likely observe the above mentioned error.

Logs:

N/A

Which branch are you using?

master (stable)

Which architecture are you using?

x86_64

Operating System:

Debian Trixie

Server/VM specifications:

N/A

Is Apparmor, SELinux or similar active?

N/A

Virtualization technology:

N/A

Docker version:

N/A

docker-compose version or docker compose version:

N/A

mailcow version:

2025-12a

Reverse proxy:

N/A

Logs of git diff:

N/A

Logs of iptables -L -vn:

N/A

Logs of ip6tables -L -vn:

N/A

Logs of iptables -L -vn -t nat:

N/A

Logs of ip6tables -L -vn -t nat:

N/A

DNS check:

N/A

[milkmaker]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.