systemd-remount-fs.service - Man Page

systemd-remount-fs​.service

/usr/lib/systemd/systemd-remount-fs

systemd-remount-fs​.service is an early boot service that applies mount options listed in fstab(5), or gathered from the partition table (when systemd-gpt-auto-generator(8) is active) to the root file system, the /usr/ file system, and the kernel API file systems​. This is required so that the mount options of these file systems — which are pre-mounted by the kernel, the initrd, container environments or system manager code — are updated to those configured in /etc/fstab and the other sources​. This service ignores normal file systems and only changes the root file system (i​.e​. /), /usr/, and the virtual kernel API file systems such as /proc/, /sys/ or /dev/​. This service executes no operation if no configuration is found (/etc/fstab does not exist or lists no entries for the mentioned file systems, or the partition table does not contain relevant entries)​.

For a longer discussion of kernel API file systems see API File Systems​^[1]​.

Note: systemd-remount-fs​.service is usually pulled in by systemd-fstab-generator(8), hence it is also affected by the kernel command line option fstab=, which may be used to disable the generator​. It may also be pulled in by systemd-gpt-auto-generator(8), which is affected by systemd​.gpt_auto and other options​.

systemd(1), fstab(5), mount(8), systemd-fstab-generator(8), systemd-gpt-auto-generator(8)

1.

API File Systems
https://systemd.io/API_FILE_SYSTEMS