Разумно недавние ядра Linux (добавленные когда-то в серии 2.6) могут расширять файловые системы ext3 / 4 в режиме онлайн (т.е. при монтировании):
localhost root # lvcreate -L100M -n test vg0 Logical volume "test" created. localhost root # mkfs.ext4 /dev/vg0/test mke2fs 1.42.13 (17-May-2015) Creating filesystem with 102400 1k blocks and 25688 inodes Filesystem UUID: 1d97763f-7a37-41cc-b2a6-c5b2f93a616a Superblock backups stored on blocks: 8193, 24577, 40961, 57345, 73729 Allocating group tables: done Writing inode tables: done Creating journal (4096 blocks): done Writing superblocks and filesystem accounting information: done localhost root # mount /dev/vg0/test /mnt/test localhost root # lvextend -L200M vg0/test Size of logical volume vg0/test changed from 100.00 MiB (25 extents) to 200.00 MiB (50 extents). Logical volume test successfully resized localhost root # resize2fs /dev/vg0/test resize2fs 1.42.13 (17-May-2015) Filesystem at /dev/vg0/test is mounted on /mnt/test; on-line resizing required old_desc_blocks = 1, new_desc_blocks = 1 The filesystem on /dev/vg0/test is now 204800 (1k) blocks long.