We have 12 machines with CentOS 7 servers ( VM servers ) where the root file system is XFS (created with ftype=0
, default CentOS setting at the time the system was installed).
And we want to install on each VM server docker service
Unfortunately, the Docker overlay2 storage driver requires that file system to have been created with ftype=1
:
One option to change the ftype to 1 is to do the following steps
- Boot into CentOS-7-x86_64-LiveGNOME-1804.iso.
- Open a terminal and sudo -s.
- Scan for LVM volumes: vgscan
- Change into the appropriate volume group (centos in my case): vgchange -ay centos
- Scan for the logical volumes in that group: lvscan
- Create a mount point for the root FS: mkdir /mnt/root
- Mount the logical volume corresponding to the root FS: mount /dev/centos/root /mnt/root
- Dump to remote host: xfsdump -J - /mnt/root | ssh 'cat >/data/rootfs.dump'
- Unmount the root FS: umount /mnt/root
- Recreate the root FS: mkfs.xfs -f -n ftype=1 /dev/centos/root
- Mount the recreated root FS: mount /dev/centos/root /mnt/root
- Restore from remote host: ssh 'cat /data/rootfs.dump' | xfsrestore -J - /mnt/root
- Reboot. Everything should be as it was before, except xfs_info / should now show ftype=1.
But we want to know what the other alternative for steps 1-13 , because steps 1-13 required downtime on the servers
Is any other approach to change the ftype
to 1 ?
For example maybe by adding additional disk to the OS and create xfs file system with ftype=1
, and allocate the docker to run on this disk?