[SOLVED] How to Resize CentOS 6.5 Partitions

TetraAsh · 10-13-2014, 04:27 AM

OK, I have a VPS server CentOS 6.5 , we have 100GB drive space available but when it was provisioned the partitions were setup as smaller partitions.

I'm not confident enough to resize these without some help.
So yeah, Help please!!!!

Preferably I would like to expand
/ -> 10GB
/usr -> 10GB
/var - > 10GB
/home -> 50GB

Below is some outputs that might be useful, I would like a guide of the commands, and maybe a link to some good reading material to let me figure out how this all works cause it seems pretty confusing to me.

Thanks in Advanced

Code:

[root@mx3 ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/xvda1            4.0G  795M  3.2G  20% /
/dev/mapper/vg00-usr  4.0G  1.5G  2.4G  39% /usr
/dev/mapper/vg00-var  4.0G  693M  3.1G  19% /var
/dev/mapper/vg00-home
                      4.0G  233M  3.6G   7% /home
none                  1.5G   64K  1.5G   1% /tmp

[root@mx3 ~]# fdisk -l

Disk /dev/xvda: 100.0 GB, 100000595968 bytes
255 heads, 63 sectors/track, 12157 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: 0xad2b2367

    Device Boot      Start         End      Blocks   Id  System
/dev/xvda1               1         523     4200966   83  Linux
/dev/xvda2             524         785     2104515   82  Linux swap / Solaris
/dev/xvda3             786       12157    91345590   8e  Linux LVM

Disk /dev/mapper/vg00-usr: 4294 MB, 4294967296 bytes
255 heads, 63 sectors/track, 522 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 /dev/mapper/vg00-var: 4294 MB, 4294967296 bytes
255 heads, 63 sectors/track, 522 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 /dev/mapper/vg00-home: 4294 MB, 4294967296 bytes
255 heads, 63 sectors/track, 522 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

[root@mx3 ~]#  cat /etc/fstab
/dev/xvda1      /               ext3    defaults,noatime        1 1
/dev/xvda2      none            swap    sw
/dev/vg00/usr   /usr            ext4    defaults,noatime        0 2
/dev/vg00/var   /var            ext4    defaults,usrquota,noatime       0 2
/dev/vg00/home  /home           ext4    defaults,usrquota,noatime       0 2
#/dev/hdd/data  /data           ext4    defaults,usrquota,noatime       0 2
devpts          /dev/pts        devpts  gid=5,mode=620  0 0
none            /proc           proc    defaults        0 0
none            /tmp    tmpfs   defaults        0 0
[root@mx3 ~]#  pvs
  PV         VG   Fmt  Attr PSize  PFree
  /dev/xvda3 vg00 lvm2 a--  87.11g 75.11g
[root@mx3 ~]# pvscan
  PV /dev/xvda3   VG vg00   lvm2 [87.11 GiB / 75.11 GiB free]
  Total: 1 [87.11 GiB] / in use: 1 [87.11 GiB] / in no VG: 0 [0   ]

rknichols · 10-13-2014, 10:25 AM

For the LVM volumes, it's easy:

Code:

lvextend --size 10G --resizefs /dev/vg00/usr
lvextend --size 10G --resizefs /dev/vg00/var
lvextend --size 50G --resizefs /dev/vg00/home

Growing the root filesystem is going to be a lot more painful. To make space, you will have to shrink the LVM physical volume (pvresize --setphysicalvolumesize 75G /dev/xvda3), then shrink the partition itself by 6G and slide it to the end of the disk (and AFAIK gparted won't allow you to move a partition that contains an LVM physical volume), delete the swap partition, resize the root partition and filesystem (gparted will do that for you), re-create the swap partition, and finally run "pvresize /dev/xvda3" to make the physical volume completely fill its partition.

It would be easier and safer to copy the existing /dev/xvda3 to another disk, then delete the existing xvda2 and xvda3 partitions, resize the root partition and filesystem, create new swap and LVM partitions, then use pvmove to move the LVM physical volume back into its new space. Still painful, though.

UPDATE: It appears that a recent enough version of gparted will allow you to resize and move an LVM physical volume, and also your swap partition. That's going to make things a lot easier. You can do the logical volume resizing as above, and then let gparted (booted from separate GParted Live media) take care of the moving and resizing needed to grow your root partition.