I'm running a centos 7 server.
I want to change the label of the root file system (xfs).
xfs_admin -L "newlabel" /dev/mapper/centos-root fails because it can't operate on a mounted filesystem.
Is it possible to change label of mounted filesystem?
Is there a way to run something like that during boot before the root fs is mounted?
The ability to update the label of a mounted XFS file system was recented added. August 2018 for upstream code and November 2018 for RHEL/CentOS 7 packages.
Update the label like this (as root):
xfs_io -c "label -s MYNEWLABEL" /MNTPOINT From the xfs_io man page:
label [ -c | -s label ]
On filesystems that support online label manipulation, get, set, or clear the filesystem label. With no options, print the current filesystem label. The -c option clears the filesystem label by setting it to the null string. The -s label option sets the filesystem label to label. If the label is longer than the filesystem will accept, xfs_io will print an error message. XFS filesystem labels can be at most 12 characters long.
For upstream code this required Linux kernel >= 4.18 and xfsprogs >= 4.17.0.
For RHEL / CentOS 7 this required packages kernel >= 3.10.0-957.el7 and xfsprogs >= 4.5.0-17.
References:
From man xfs_admin
Devices that are mounted cannot be modified. Administrators must unmount filesystems before xfs_admin or xfs_db(8) can convert parameters. A number of parameters of a mounted filesystem can be examined and modified using the xfs_growfs(8) command.
