we have rhel 7.2 server with docker service and docker container
docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
9fcdfcd76932 linux-exporter:v1.2.0 "/bin/linux_exporter…" 3 days ago Up 3 days linux-exporter
from the dmesg we get many lines with Unmounting Filesystem / Mounting V4 Filesystem
as the following
[Wed Dec 23 05:52:11 2020] XFS (dm-4): Ending clean mount
[Wed Dec 23 05:52:12 2020] XFS (dm-4): Unmounting Filesystem
[Wed Dec 23 05:53:12 2020] XFS (dm-4): Mounting V4 Filesystem
[Wed Dec 23 05:53:12 2020] XFS (dm-4): Ending clean mount
[Wed Dec 23 05:53:13 2020] XFS (dm-4): Unmounting Filesystem
[Wed Dec 23 05:54:13 2020] XFS (dm-4): Mounting V4 Filesystem
[Wed Dec 23 05:54:13 2020] XFS (dm-4): Ending clean mount
[Wed Dec 23 05:54:14 2020] XFS (dm-4): Unmounting Filesystem
[Wed Dec 23 05:55:14 2020] XFS (dm-4): Mounting V4 Filesystem
[Wed Dec 23 05:55:14 2020] XFS (dm-4): Ending clean mount
[Wed Dec 23 05:55:15 2020] XFS (dm-4): Unmounting Filesystem
[Wed Dec 23 05:56:15 2020] XFS (dm-4): Mounting V4 Filesystem
[Wed Dec 23 05:56:15 2020] XFS (dm-4): Ending clean mount
[Wed Dec 23 05:56:16 2020] XFS (dm-4): Unmounting Filesystem
[Wed Dec 23 05:57:16 2020] XFS (dm-4): Mounting V4 Filesystem
[Wed Dec 23 05:57:16 2020] XFS (dm-4): Ending clean mount
[Wed Dec 23 05:57:17 2020] XFS (dm-4): Unmounting Filesystem
[Wed Dec 23 05:58:17 2020] XFS (dm-4): Mounting V4 Filesystem
[Wed Dec 23 05:58:17 2020] XFS (dm-4): Ending clean mount
[Thu Dec 24 05:13:42 2020] XFS (dm-4): Unmounting Filesystem
[Thu Dec 24 05:13:42 2020] device-mapper: thin: Deletion of thin device 44 failed.
[Thu Dec 24 05:13:43 2020] device-mapper: ioctl: remove_all left 4 open device(s)
[Thu Dec 24 05:13:45 2020] XFS (dm-4): Mounting V4 Filesystem
[Thu Dec 24 05:13:45 2020] XFS (dm-4): Ending clean mount
[Thu Dec 24 05:13:45 2020] XFS (dm-4): Unmounting Filesystem
[Thu Dec 24 05:13:46 2020] XFS (dm-4): Mounting V4 Filesystem
[Thu Dec 24 05:13:46 2020] XFS (dm-4): Ending clean mount
[Thu Dec 24 05:13:46 2020] XFS (dm-4): Unmounting Filesystem
[Thu Dec 24 05:13:46 2020] XFS (dm-4): Mounting V4 Filesystem
[Thu Dec 24 05:13:46 2020] XFS (dm-4): Ending clean mount
we checked the info from xfs_info
xfs_info /var/lib/docker
meta-data=/dev/mapper/vg-linux_var isize=256 agcount=26, agsize=1039872 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0 finobt=0
data = bsize=4096 blocks=26441728, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
what we can see is that ftype=0 when we have rhel 7.2
but not sure if this related to our problem
