Remove hardlinked folder sync on btrfs

[geohei]

Hi.

This is too bad. Probably an admin (who doesn't participate anymore in NAS administration) did a hardlink or btrfs tweak, which he didn't communicate.

A folder is mirrored from one shared folder to another one.

I see:

$ mount
...
/dev/mapper/vg1-volume_1 on /volume1/homes/mad/myData type btrfs (rw,relatime,synoacl,space_cache=v2,auto_reclaim_space,metadata_ratio=50,subvolid=265,subvol=/@syno/Data/myData)

1. Is it possible that this was done using the DSM (6.2.4) or was a shell command required to achieve this?
2. How can I revert this action = split the link?

Thanks

 

[geohei]

I found the problem.
It was a forgotten (undocumented) script /usr/local/etc/S99mount.sh, which created the links as follows:

/bin/mkdir -p "$2"
/bin/mount -o bind "$1" "$2"
/usr/syno/bin/synologset1  sys info 0x11800000 "$0: Mounted $1 to $2"

After removing that script that, the btrfs subvolume was gone (after restart).