自作amiなどからec2インスタンスを起動したら、設定したディスク容量よりも小さかった時の対応

aws

結論、resize2fs する。

20GB 割り当てたはずなのに….
8GB程度しか割りあたってない...

[root@centos6-base ~]# df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/xvde       7.8G  2.1G  5.3G  29% /
tmpfs           296M     0  296M   0% /dev/shm


ディスクサイズは20GB割り当てられていることがわかる。

[root@centos6-base ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
xvde 202:64   0  20G  0 disk /

結論目的のディスクをresize2fs してやればよかった。

[root@centos6-base ~]# resize2fs /dev/xvde
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/xvde is mounted on /; on-line resizing required
old desc_blocks = 1, new_desc_blocks = 2
Performing an on-line resize of /dev/xvde to 5242880 (4k) blocks.

The filesystem on /dev/xvde is now 5242880 blocks long.

ディスク容量を確認する

[root@centos6-base ~]# df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/xvde        20G  2.1G   17G  12% /
tmpfs           296M     0  296M   0% /dev/shm

resize2fs する前に調べたこと

fdisk しなきゃならないのかどうか、ひとまず確認

[root@centos6-base ~]# fdisk /dev/xvde
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0xe1b7a5f5.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.

Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

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): p

Disk /dev/xvde: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xe1b7a5f5

    Device Boot      Start         End      Blocks   Id  System
resize2fs 後のディスク
[root@centos6-base ~]# fdisk /dev/xvde -l

Disk /dev/xvde: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk identifier が違うくらい..?

参考
http://blog.suz-lab.com/2012/11/cdp-snapshot-v2-ec2-linuxfsck-ec2.html