New problem in >18.04...
I just discovered that the way I've always used fsck at the root access in recovery mode no longer works. It used to be:
fsck -f /
But now it tells me that the disk is mounted r/w, and it won't run. Sure enough the disk IS mounted r/w. This is new behavior. Trying to remount the disk as ro doesn't work either.
mount -o remount,ro /
And, running fsck from the recovery mode menus doesn't work either.
Running fsck while booted to a Ubuntu Live USB works of course.
Anybody got an idea why I can't fsck in recovery mode, and what's changed that causes the disk to be mounted r/w?