Hi, Recently, I met a problem when extending ext4. At first, I cannot format ext4 more than 16T, then I upgraded e2fsprogs to version 1.43.7 which is the latest stable version. I can create more than 16T by command: mke2fs -O 64bit -t ext4 /dev/mapper/xxx After format it, I mount it under folder /nfs/xxx, it works good. Then I find I cannot extend it online, steps: 1. lvextend to extend LVM size 2. resize2fs /dev/mapper/xxx, it reports cannot online resize 3. "dumpe2fs /dev/mapper/xxx | grep feature" command shows this filesystem has no resize_inode flag I tried many times and find if I created more than 16T, it has no resize_inode flag, seems they are opposite, cannot enable at the same time. I find this page: https://bugzilla.redhat.com/show_bug.cgi?id=982871 According to this page, it seems on rhel7, it should be able to enlarge online, but unfortunately, I failed on rhel6 and I can only have rhel6. If I umount /nfs/xxx first, then resize2fs can work expectedly, however, this indicates we must stop our service for about 15~30 minutes. This is what I do not want. Then I see there is an old patch talking about this issue: https://patchwork.ozlabs.org/patch/256822/ >From this patch, it seems that extend ext4 for more than 16T is possible, but I always fail on redhat 6.7. At last, let me make a summary of my question: 1. if I create an ext4 FS more than 16T, it has no resize_inode flag, so I cannot extend it online 2. if I create an ext4 FS less than 16T, even with -O 64bit option, I cannot extend it to more than 16T, I tried online and offline Please suggest, thank you very much.
