Recently had a LVM'd CentOS 6.5 install get accidentally cold-shutdown.  On bootup, it says that the home partition need fscking:/dev/mapper/vg_myserver-lv_home: Block bitmap for group 3072 is not in group.  (block 3335668205)/dev/mapper/vg_myserver-lv_home: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY....but I guess the root partition is OK, since it gives me a shell there.  So we run e2fsck -b 32768 /dev/mapper/vg_myserver/lv_home and after saying Yes to various fixes, on Pass 5 it just prints endless numbers to the screen, very fast.  Once in a while it will print them in neat columns, and if these are block numbers, after a couple hours we are still nowhere near the first 2% being done of our 1.2 TB LV.I read that you can use cleap_mmp with tune2fs, but upon trying that, it doesn't accept cleap_mmp nor list it among valid options.My question is, how does everyone deal with a corrupt ext4 fs without weeks of downtime?  Does everyone have this dilemma, or weeks of downtime vs rebuilding your server / lost data?  If so why does anyone use or recommend the use of ext4?  Is there some trick I'm missing that would let me target the specific block/group it's complaining about, so we can get on with it and mount the home fs again?
targeting a specific block with e2fsck to shorten wait
linux;centos;lvm;ext4;fsck
Run e2fsck -y to say yes to all questions automatically instead of having to manually say yes a million times.