Rsync: Software caused connection abort (103)

Nextcloud version (eg, 20.0.5): 28.0.1
Operating system and version (eg, Ubuntu 20.04): Linux 6.1.0-rpi8-rpi-v8 aarch64
Apache or nginx version (eg, Apache 2.4.25): Apache/2.4.58
PHP version (eg, 7.4): 8.1.27

The issue you are facing:
I think my mount-point fails during rsync. The output from rsync is this:

sending incremental file list
rsync: [sender] opendir "/tmp/borg/20240111_181442-nextcloud-aio" failed: Software caused connection abort (103)
rsync: [sender] opendir "/tmp/borg/20240128_040059-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240131_040111-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240204_040119-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240211_040117-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240218_040101-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240219_040102-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240220_040103-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240221_040106-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240222_040107-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240223_040106-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240224_040104-nextcloud-aio" failed: Transport endpoint is not connected (107)
rsync: [sender] opendir "/tmp/borg/20240225_040053-nextcloud-aio" failed: Transport endpoint is not connected (107)
borg/
borg/20240225_040053-nextcloud-aio/

sent 651 bytes  received 36 bytes  274,80 bytes/sec
total size is 0  speedup is 0,00 (DRY RUN)
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1338) [sender=3.2.7]

And then when I

ls -l /tmp/

My mount-point seems to have really crashed

d????????? ? ?    ?       ?            ? borg

Rsync works fine as I already successfully rsync files to this other raspberry pi (192.168.1.119) on a regular basis.

Is this the first time you’ve seen this error? (Y/N): Y

Steps to replicate it:

  1. Follow this guide: GitHub - nextcloud/all-in-one: The official Nextcloud installation method. Provides easy deployment and maintenance with most features included in this one Nextcloud instance.
  2. Run this command: sudo borg mount “/mnt/backup/borg” /tmp/borg/
  3. Supply password to the encrypted backup
  4. Run: sudo rsync -anvhP -e “ssh -i /home/username/.ssh/id_rsa -p nnnn” /tmp/borg username@192.168.1.119:~/nextcloud_borg_mirror/

I solved this issue. It was my locales settings that were messed up. Switched them to some utf-8 and now it works.

Thread where I found the solution: rsync from a borg mount throws "Transport endpoint is not connected" · Issue #2595 · borgbackup/borg · GitHub