unable to resize root partition on EC2 centos [closed]

Question

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.

Answer 1

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! 

Answer 2

The following steps very simple works very well for me:

# lsblk NAME    MAJ:MIN RM SIZE RO TYPE MOUNTPOINT xvda    202:0    0  30G  0 disk  └─xvda1 202:1    0   8G  0 part / 

Perform the following command as root:

# yum install cloud-utils-growpart  # growpart /dev/xvda 1  # reboot 

After the reboot:

# lsblk NAME    MAJ:MIN RM SIZE RO TYPE MOUNTPOINT xvda    202:0    0  30G  0 disk  └─xvda1 202:1    0  30G  0 part /