Please reveal a way using the e2fsprogs tools to do this: copy the known-good primary superblock to all backup superblocks I accept unmounting the filesystem first. This way I can add that step to my shutdown scripts and avoid those new e2fscks on cleanly unmounted filesystems that take many hours on my filesystems due to feature flag mismatches. I couldn't find any switch for tune2fs to set flags on backup superblocks, it seems to only work on the primary superblock. I'm using e2fsprogs-1.40.6