Before you begin
Step 1
Check the current storage space using the df -h command.
| [root@localhost ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/centos-root 38G 21G 18G 54% / devtmpfs 1.2G 0 1.2G 0% /dev tmpfs 1.2G 0 1.2G 0% /dev/shm tmpfs 1.2G 24M 1.2G 2% /run tmpfs 1.2G 0 1.2G 0% /sys/fs/cgroup /dev/sda1 497M 189M 308M 39% /boot tmpfs 234M 0 234M 0% /run/user/0 |
Take a note of the LVM name you are extending. This is mounted on / in the above output.
In this example, we are extending /dev/mapper/centos-root.
Step 2
Determine what type of file system structure is in place using fdisk -l.
|
[root@localhost ~]# fdisk -l Disk /dev/sda: 107.4 GB, 107374182400 bytes, 209715200 sectors Device Boot Start End Blocks Id System Disk /dev/mapper/centos-swap: 2147 MB, 2147483648 bytes, 4194304 sectors Disk /dev/mapper/centos-root: 40.3 GB, 40273707008 bytes, 78659584 sectors |
In this example, we are extending sda. Take note of the partition number which is labeled as Linux LVM under the System column and the number in the Start as these will be needed soon.
In this example, the partition number is sda2 and the Start is 1026048.
Extending the Partition Using fdisk
Step 1
Start modifying the parameters of the drive by using fdisk [drive].
| [root@localhost ~]# fdisk /dev/sda Welcome to fdisk (util-linux 2.23.2).Changes will remain in memory only, until you decide to write them. Be careful before using the write command. |
p at the prompt.Step 2
Delete the partition by typing d then pressing enter.
| Command (m for help): d |
Step 3
Specify the partition number and press enter.
| Partition number (1,2, default 2): 2 Partition 2 is deleted |
Step 4
Type n to add a partition.
| Command (m for help): n Partition type: p primary (1 primary, 0 extended, 3 free) e extended |
Step 5
Select the type as Primary by typing p then pressing enter.
| Select (default p): p |
Step 6
Type the same partition number that you just deleted.
| Partition number (2-4, default 2): 2 |
Step 7
Specify the first sector by typing the number which was previously under the "Start" column.
In this example, that was 1026048.
| First sector (1026048-209715199, default 1026048): 1026048 |
Step 8
At the next prompt, just press enter to use the full available disk space.
| Last sector, +sectors or +size{K,M,G} (1026048-209715199, default 209715199): Using default value 209715199 Partition 2 of type Linux and of size 99.5 GiB is set |
Step 9
Next, change the partition type by typing t and pressing enter.
| Command (m for help): t |
Step 10
Specify the partition number again and press enter.
| Partition number (1,2, default 2): 2 |
Step 11
When prompted for a Hex code, enter 8e which is Linux LVM.
| Hex code (type L to list all codes): 8e Changed type of partition 'Linux' to 'Linux LVM' |
Step 12
Confirm the change is correct by entering p to print out the new partition table.
|
Command (m for help): p Disk /dev/sda: 107.4 GB, 107374182400 bytes, 209715200 sectors Device Boot Start End Blocks Id System |
Step 13
Exit and write the change.
| Command (m for help): w The partition table has been altered!Calling ioctl() to re-read partition table. |
You may get this warning when you try to write the 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.
If you get this message, a restart of the server will be required.
Step 14
Check the partition table to ensure the changes have taken effect by running fdisk -l again.
|
[root@localhost ~]# fdisk -l Disk /dev/sda: 107.4 GB, 107374182400 bytes, 209715200 sectors Device Boot Start End Blocks Id System Disk /dev/mapper/centos-swap: 2147 MB, 2147483648 bytes, 4194304 sectors Disk /dev/mapper/centos-root: 40.3 GB, 40273707008 bytes, 78659584 sectors |
Step 15
Proceed to the section Extending the Volume further down in this article.
Extending the Partition Using parted
These steps will need to be following if you get the following message when you run fdisk -l.
| WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. |
Step 1
Open parted by running parted.
| [root@localhost ~]# parted GNU Parted 2.1 Using /dev/sda Welcome to GNU Parted! Type 'help' to view a list of commands. |
Step 2
Change the units to sectors by typing u s then pressing enter.
| (parted) u s |
Step 3
View the partition. When you do this, you will get a message similar to the following:
| (parted) p Warning: Not all of the space available to /dev/sda appears to be used, you can fix the GPT to use all of the space (an extra 440401920 blocks) or continue with the current setting? |
Choose to fix this by typing f and pressing enter.
| Fix/Ignore? f Model: Msft Virtual Disk (scsi) Disk /dev/sda: 524288000s Sector size (logical/physical): 512B/4096B Partition Table: gptNumber Start End Size File system Name Flags 1 2048s 1048576s 1046529s ext3 primary boot 2 1050624s 83884031s 82833408s primary lvm |
Step 4
From the above output of Step 3, look at the partition with the "lvm" flag. Take note of the start sector for that partition found under the start column and the total sector size which is next to the disk letter.
In this case, the start is 1050624 and the total is 524288000. Also take note of the name.
Step 5
Delete the partition by typing rm followed by the partition number.
| (parted) rm 2 Warning: WARNING: the kernel failed to re-read the partition table on /dev/sda (Device or resource busy). As a result, it may not reflect all of your changes until after reboot. |
Step 6
Recreate the partition by typing mkpart and pressing enter.
| (parted) mkpart |
Step 7
Call the partition the same name as before.
| Partition name? []? primary |
Step 8
Leave the file system type as the default by just pressing enter.
| File system type? [ext2]? |
Step 9
Enter the start sector as noted earlier.
| Start? 1050624 |
Step 10
Enter the total sectors minus 1.
In this case, we take 524288000 and minus one to get 524287999.
| End? 524287999 Warning: You requested a partition from 1050624s to 524287999s. The closest location we can manage is 1050624s to 524287966s. Is this still acceptable to you? |
Step 11
You will get the above warning saying the partition is too large and offer to set it to the largest possible. Say yes to this. Note that this step can take some time to finish.
| Yes/No? y Warning: WARNING: the kernel failed to re-read the partition table on /dev/sda (Device or resource busy). As a result, it may not reflect all of your changes until after reboot. |
Step 12
Modify the flag of the recreated partition to lvm by typing t [partition number] lvm.
| (parted) t 2 lvm Warning: WARNING: the kernel failed to re-read the partition table on /dev/sda (Device or resource busy). As a result, it may not reflect all of your changes until after reboot. |
Step 13
Confirm your changes are correct by printing the partition table with p.
| (parted) p Model: Msft Virtual Disk (scsi) Disk /dev/sda: 524288000s Sector size (logical/physical): 512B/4096B Partition Table: gptNumber Start End Size File system Name Flags 1 2048s 1048576s 1046529s ext3 primary boot 2 1050624s 524287966s 523237343s primary lvm |
Step 14
Quit gparted by typing q.
| (parted) q Information: You may need to update /etc/fstab. |
Step 15
Reboot your server.
Extending the Volume
Step 1
Make sure the partition is currently a listed Physical Volume with pvdisplay.
| [root@localhost ~]# pvdisplay --- Physical volume --- PV Name /dev/sda2 VG Name centos PV Size 39.51 GiB / not usable 2.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 10114 Free PE 0 Allocated PE 10114 PV UUID NP5SVJ-xEhi-hEd9-sMZs-6DGe-VDOi-zuIetu |
Step 2
Extend the Physical Volume with pvresize [partition].
| [root@localhost ~]# pvresize /dev/sda2 Physical volume "/dev/sda2" changed 1 physical volume(s) resized / 0 physical volume(s) not resized |
Step 3
View the current Logical Volumes with lvdisplay.
| [root@localhost ~]# lvdisplay --- Logical volume --- LV Path /dev/centos/swap LV Name swap VG Name centos LV UUID w7zRnQ-0TCm-IIJF-dMR4-ypNL-HxZV-tO90iu LV Write Access read/write LV Creation host, time localhost, 2014-10-06 08:56:38 +0000 LV Status available # open 2 LV Size 2.00 GiB Current LE 512 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:0--- Logical volume --- LV Path /dev/centos/root LV Name root VG Name centos LV UUID gaqFxq-HmdB-Msdc-DH32-qgz0-BafH-xERhST LV Write Access read/write LV Creation host, time localhost, 2014-10-06 08:56:39 +0000 LV Status available # open 1 LV Size 37.51 GiB Current LE 9602 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:1 |
Step 4
Take note of the LV path of the Logical Volume you are extending. It will be similar but not necessarily the same as the name found in step one.
In this example, the name in step one was /dev/mapper/centos-root meaning the path is /dev/centos/root.
Step 5
Extend the logical volume to use all the new space by running:
lvextend -l+100%FREE [Logical Volume]
| [root@localhost ~]# lvextend -l+100%FREE /dev/centos/root Size of logical volume centos/root changed from 37.51 GiB (9602 extents) to 97.51 GiB (24962 extents). Logical volume root successfully resized. |
Step 6
Resize the file system to use the new space. Please note that this is different depending on the server you are working on. Both of the following commands will take a while to complete. Do not interrupt them.
On CloudNX Cloud and Virtual Private Servers run the command:
xfs_growfs [Logical Volume].
| [root@localhost ~]# xfs_growfs /dev/centos/root meta-data=/dev/mapper/centos-root isize=256 agcount=9, agsize=1147392 blks = sectsz=512 attr=2, projid32bit=1 = crc=0 finobt=0 data = bsize=4096 blocks=9832448, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=0 log =internal bsize=4096 blocks=2560, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 data blocks changed from 9832448 to 25561088 |
On Bare Metal, Legacy Cloud and Legacy Virtual servers run:
resize2fs [Logical Volume].
| [root@localhost ~]# resize2fs /dev/centos/root resize2fs 1.42.9 (28-Dec-2013) Filesystem at /dev/centos/root is mounted on /; on-line resizing required old desc_blocks = 3, new_desc_blocks = 16 Performing an on-line resize of /dev/VolGroup00/LogVol00 to 25561088 (4k) blocks. The filesystem on /dev/centos/root is now 25561088 blocks long. |
Step 7
Confirm the space has been added with df -h.
| [root@localhost ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/centos-root 98G 21G 78G 21% / devtmpfs 1.2G 0 1.2G 0% /dev tmpfs 1.2G 0 1.2G 0% /dev/shm tmpfs 1.2G 8.5M 1.2G 1% /run tmpfs 1.2G 0 1.2G 0% /sys/fs/cgroup /dev/sda1 497M 189M 308M 39% /boot tmpfs 234M 0 234M 0% /run/user/0 |