I have done resize on our MDT quite a few times without any problem. I did the following to resize the MDT: e2fsck -f /dev/mdtvg/mdt lvextend --size +40G /dev/mdtvg/mdt e2fsck -f /dev/mdtvg/mdt resize2fs /dev/mdtvg/mdt e2fsck -f /dev/mdtvg/mdt Nirmal