i created my EC2 Machine using Community Image of Centos 6.3 x64. i have added a 35 GB disk. Now when i do #df -h
Filesystem Size Used Avail Use% Mounted on
/dev/xvda1 7.9G 1.2G 6.4G 16% /
tmpfs 7.3G 0 7.3G 0% /dev/shm
my disk is 35GB but its showing 8 GB in root and 7 as tmpfs.
i tried to use resize2fs but it didnt work on centos. disk has ext4 partation..
# resize2fs /dev/xvda
resize2fs 1.41.12 (17-May-2010)
resize2fs: Device or resource busy while trying to open /dev/xvda
Couldn't find valid filesystem superblock.
or even if i tried resize2fs /dev/xvda1 it says device has nothing to do.
any idea or other way, its my root disk(/). so cant unmount it.
i found a way to do that, resize2fs not working in case not sure why but it says device or resource busy. i found a very good article on resizedisk using fdisk we can increase block size by deleting and creating it and Make the partition bootable. all it requires is a reboot. it wont effect your data if you use same start cylinder.
# df -h <<1>>
Filesystem Size Used Avail Use% Mounted on
/dev/xvda1 6.0G 2.0G 3.7G 35% /
tmpfs 15G 0 15G 0% /dev/shm
# fdisk -l <<2>>
Disk /dev/xvda: 21.5 GB, 21474836480 bytes
97 heads, 17 sectors/track, 25435 cylinders
Units = cylinders of 1649 * 512 = 844288 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0003b587
Device Boot Start End Blocks Id System
/dev/xvda1 * 2 7632 6291456 83 Linux
# fdisk /dev/xvda <<3>>
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): u <<4>>
Changing display/entry units to sectors
Command (m for help): p <<5>>
Disk /dev/xvda: 21.5 GB, 21474836480 bytes
97 heads, 17 sectors/track, 25435 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0003b587
Device Boot Start End Blocks Id System
/dev/xvda1 * 2048 12584959 6291456 83 Linux
Command (m for help): d <<6>>
Selected partition 1
Command (m for help): n <<7>>
Command action
e extended
p primary partition (1-4)
p <<8>>
Partition number (1-4): 1 <<9>>
First sector (17-41943039, default 17): 2048 <<10>>
Last sector, +sectors or +size{K,M,G} (2048-41943039, default 41943039): <<11>>
Using default value 41943039
Command (m for help): p <<12>>
Disk /dev/xvda: 21.5 GB, 21474836480 bytes
97 heads, 17 sectors/track, 25435 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0003b587
Device Boot Start End Blocks Id System
/dev/xvda1 2048 41943039 20970496 83 Linux
Command (m for help): a <<13>>
Partition number (1-4): 1 <<14>>
Command (m for help): w <<15>>
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
# reboot <<16>>
<wait>
# df -h <<17>>
Filesystem Size Used Avail Use% Mounted on
/dev/xvda1 20G 2.0G 17G 11% /
tmpfs 15G 0 15G 0% /dev/shm
# resize2fs /dev/xvda1 <<18>>
resize2fs 1.41.12 (17-May-2010)
The filesystem is already 5242624 blocks long. Nothing to do!