https://www.howtoing.com/how-to-recover-from-file-system-corruption-using-freebsd-s-single-user-mode/
cat / etc / fstab
list the first item shows the UFS filesystem which is what we were looking for. Now, you can run the following command to perform a file system check on this disk.
-YF the fsck / dev / GPT / the rootfs
(/ dev / GPT / replace the rootfs path list)