I have a very large partition (15TB) formated with the XFS filesystem that I want to expand to 30TB. This partition was created with Parted to use GPT, which fdisk does not support. The problem with this is Parted automatically will expand the underlying filesystem when resizing a partition, but it does not support XFS. The slightly advanced solution is not hard, you just have to be careful.

To start with let me say, if you are not somewhat experienced with filesystems and partition tables, please do not attempt this. I am not responsible if you hose your system.

With that out of the way, we will be deleting the partion table, recreating it with the same starting boundary and then expanding the filesystem. When you modify the partition table, it does not necessarily change the data stored on the partition. You can delete it and then recreate it with the same boundaries and not hurt the data. It is extremely important that you line your partition on the same boundaries or you can over-write existing data. So by creating a new partition with the same starting boundary and extending it past any written data, we are ensuring that the boundaries line up properly.

I have already completed my own partition and filesystems resizing, so I will by using a flash drive as an example. The method is the same, just smaller sizes.

First examine the device. As you can see, I have roughly a 4GB partition. To resize the partition, you must first unmount it.

[cpowell@cp-linuxsvr] ~ $ sudo parted /dev/sdd
GNU Parted 2.2
Using /dev/sdd
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p                                                                
Model: Corsair Flash Voyager (scsi)
Disk /dev/sdd: 8087MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
 
Number  Start  End     Size    Type     File system  Flags
 1      512B   4043MB  4043MB  primary  XFS

Now the to reiterate, the most important thing is to line up the starting boundary of the partition. The problem shown above, is the Start 512B is listed in bytes. You might get away using that as the starting boundary, but it is not accurate enough for me to feel safe. We must change the units to sectors so we can see the exact sector used as the starting boundary.

(parted) help unit
  unit UNIT                                set the default unit to UNIT
 
	UNIT is one of: s, B, kB, MB, GB, TB, compact, cyl, chs, %, kiB, MiB, GiB, TiB
(parted) unit s  
(parted) p                                                                
Model: Corsair Flash Voyager (scsi)
Disk /dev/sdd: 15794176s
Sector size (logical/physical): 512B/512B
Partition Table: msdos
 
Number  Start  End       Size      Type     File system  Flags
 1      1s     7897087s  7897087s  primary  XFS

As you can see, if you run help unit, it lists all the available units with compact being the default. We then set the unit to s and print out the partition table again. You can see now the exact sector it starts on, 1s.

Now to remove the existing partition and create a new one using the entire device.

(parted) rm 1                                                           
(parted) mkpart primary 1s 100%
(parted) p                                                                
Model: Corsair Flash Voyager (scsi)
Disk /dev/sdd: 15794176s
Sector size (logical/physical): 512B/512B
Partition Table: msdos
 
Number  Start  End        Size       Type     File system  Flags
 1      1s     15794175s  15794175s  primary  XFS
(parted) unit compact
(parted) p                                                                
Model: Corsair Flash Voyager (scsi)
Disk /dev/sdd: 8087MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
 
Number  Start  End     Size    Type     File system  Flags
 1      512B   8087MB  8087MB  primary  XFS

There is alot happening above, so lets walk through it. First we are deleting partition 1, rm 1. We then create a new primary partition with a starting boundary of 1s and to extend to use 100% of the device. I then print out the partition table again, but because the units are still in s, it is hard to determine size so I change to a more user friendly output unit (compact) and print it out again. You can now see partition extends to 8GBs. Now we can grow out the underlying filesystem.

To grow out an XFS filesystem, you must mount it first. Remember, that you can always grow with XFS, but you cannot shrink. Below, you see that even though the partition is 8GB, the filesystem is only using 4GB.

[cpowell@cp-linuxsvr] ~ $ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sdd1             3.8G  4.2M  3.8G   1% /mnt/tmp

Growing with XFS is simple. xfs_growfs mount_point This will grow out the mounted filesystem to use the remainder of the partition, if you wish to do something more fancy please consult the man pages.

[cpowell@cp-linuxsvr] ~ $ sudo xfs_growfs /mnt/tmp
meta-data=/dev/sdd1              isize=256    agcount=4, agsize=246784 blks
         =                       sectsz=512   attr=2
data     =                       bsize=4096   blocks=987135, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=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 987135 to 1974271
[cpowell@cp-linuxsvr] ~ $ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sdd1             7.6G  4.3M  7.6G   1% /mnt/tmp

The filesystem is now expanded to ~8GB utilizing the entire device.