it is IMPOSSIBLE that /mnt/data is in use, there are ALL services stopped, all bind-mounts unmounted and only sshd is running beside systemd - how can it be that there is anything open while there is no process and "lsof" has no output to any open file? [root@rh:~]$ ps aux | grep -v "\[" USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 1 0.0 0.0 48084 4876 ? Ss 16:44 0:03 /usr/lib/systemd/systemd root 8307 0.0 0.0 33260 1508 ? Ss 18:37 0:00 /usr/lib/systemd/systemd-journald root 8309 0.0 0.0 81868 3300 ? Ss 18:37 0:00 /usr/sbin/sshd -D root 8386 0.0 0.0 126300 4716 ? Ss 18:37 0:00 sshd: root@pts/0 root 8388 0.1 0.0 116048 3980 pts/0 Ss 18:37 0:00 -bash root 8676 0.0 0.0 115720 1212 pts/0 R+ 18:39 0:00 ps aux [root@rh:~]$ df Dateisystem Typ Größe Benutzt Verf. Verw% Eingehängt auf /dev/md1 ext4 29G 6,8G 23G 24% / /dev/md2 ext4 3,6T 2,2T 1,4T 62% /mnt/data [root@rh:~]$ umount /mnt/data umount: /mnt/data: target is busy. (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1))
Please, try LIBMOUNT_DEBUG=0xffff umount /mnt/data you can also see strace -e umount,umount2 umount /mnt/data output to verify the umount syscall failed.
Created attachment 605656 [details] output of mentioned commands recdirected (stdout + errout)
Reassigning to util-linux, I don't see any connection with coreutils.
26595: libmount: CXT: [0x7f6415c7c040]: umount(2) [target='/mnt/data', flags=0x00000000] 26595: libmount: CXT: [0x7f6415c7c040]: umount(2) failed [errno=16] It does not seem like umount(8) problem, according to kernel the mountpoint is really busy... what about dmesg output? Maybe you have any loop device, running process, whatever. # dmesg # lsblk # losetup -a
go up to my initial report there are only 5 processes including systemd, sshd and my shell there are unmounted ANY bind-mounts for the raid10-array so how the hell can there be any open files? and no, sitting in front of the machine and killing even sshd does not change anything expect the final count of THREE prcoesses: systemd, systemd-journald and my bash in /root
Well, it does not have to be a problem with open files or running processes. The device may be referenced internally by kernel (see for example bug #808795).
Are you able to reproduce the problem with the latest kernel and util-linux?
i will try this ASAP and give feedback, currently raid-check is running on my 4 TB RAID10 i liked to unmount for "fsck -Df"
fine - with latest kernel and util-linux (always updates-testing on it works) [root@rh:~]$ fsck.ext4 -Df /dev/md2 e2fsck 1.42.3 (14-May-2012) Durchgang 1: Prüfe Inodes, Blocks, und Größen data: |== | 4.2%