You cannot create a Linux partition larger than 2 TB using the fdisk command. Using fdisk you could not create partitions larger than 2 TB. It is fine for desktop and laptop users, but for servers, you need large partitions like 2TB, 3TB, 4TB etc.
Root Cause
- The fdisk command only supports the legacy MBR partition table format (also known as msdos partition table)
- MBR partition tables use data fields that have a maximum of 32-bit sector numbers, and with 512 bytes/sector that means a maximum of 2^(32+9) bytes per disk or partition is supported
- MBR partition table can not support accessing data on disks past 2.19TB due to the above limitation
- Note that some older versions of fdisk may permit a larger size to be created but the resulting partition table will be invalid.
- The parted command can create disk labels using MBR (msdos), GUID Partition Table (GPT), SUN disk labels and many more types.
- The GPT disk label overcomes many of the limitations of the DOS MBR including restrictions on the size of the disk, the size of any one partition and the overall number of partitions.
- Note that booting from a GPT labelled volume requires firmware support and this is not commonly available on non-EFI platforms (including x86 and x86_64 architectures).
For more details please see the solution on Red Hat Customer Portal
Create a Logical Volume larger than 2TB and format it in Linux/RHEL
When we need more space on a server. To get more space we create new virtual LUNs from our storage and present that LUN on the server to get the required space.
After exporting the LUNs to a server we need to create Physical Volume, Volume Group, and Logical Volume and then we format the logical volume using a file system. Linux supports numerous file systems, but common choices for the system disk on a block device include the ext* family (ext2, ext3 and ext4), XFS, JFS, ReiserFS and btrfs. ext4 is the latest file system of ext* family.
After formatting the Logical Volume we can mount this on a directory (mount point) and can use the disk as per our requirements.
Rescan the Disks:
If you added a new disk to the system or exported a virtual volume from your storage then rescan the disks to find the new disk. Here I have added a new virtual volume from my 3PAR storage /dev/mapper/mpathj. Multipath is enabled in this case so you need to scan the disk corresponding to each and every host. Use command ls /sys/class/scsi_host to see the list of hosts.
[root@server ~]# ls /sys/class/scsi_host
host0 host1 host10 host11 host12 host2 host3 host4 host5 host6 host7 host8 host9
Now use the below command to scan the newly added LUN for all the hosts:
[root@server ~]# echo '- - -' > /sys/class/scsi_host/host0/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host1/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host2/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host3/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host4/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host5/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host6/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host7/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host8/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host9/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host10/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host11/scan [root@server ~]# echo '- - -' > /sys/class/scsi_host/host12/scan
Now use the command I -l or multipath -ll to find the appropriate disk which you have added. You can identify the disk by the size of the disk or by using the WWN number. fdisk -l will show the multiple disks but you have to use the disk which will be like /dev/mapper/mpathX, in my case it is dev/mapper/mpathj.
[root@server ~]# fdisk -l Disk /dev/mapper/mpathi: 1099.5 GB, 1099511627776 bytes 255 heads, 63 sectors/track, 133674 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 16384 bytes / 16777216 bytes Disk identifier: 0xaedc5bdb Device Boot Start End Blocks Id System /dev/mapper/mpathip1 3 133674 1073720340 83 Linux Partition 1 does not start on physical sector boundary. Disk /dev/mapper/mpathj: 3298.5 GB, 3298534883328 bytes 255 heads, 63 sectors/track, 401024 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 16384 bytes / 16777216 bytes Disk identifier: 0x00000000
[root@server ~]# multipath -ll mpathj (360002ac00000000001003c5500010b4b) dm-17 3PARdata,VV size=3.0T features='0' hwhandler='0' wp=rw `-+- policy='round-robin 0' prio=1 status=active |- 1:0:2:7 sdae 65:224 active ready running |- 2:0:2:7 sdag 66:0 active ready running |- 1:0:0:7 sdad 65:208 active ready running `- 2:0:0:7 sdaf 65:240 active ready running mpathi (360002ac00000000000006f2900010b4b) dm-6 3PARdata,VV size=1.0T features='0' hwhandler='0' wp=rw `-+- policy='round-robin 0' prio=1 status=active |- 1:0:0:6 sdh 8:112 active ready running |- 2:0:0:6 sdv 65:80 active ready running |- 1:0:2:6 sdo 8:224 active ready running `- 2:0:2:6 sdac 65:192 active ready running
Partition of the Newly Added Disk:
- Use the parted tool to access the partition table of the device:
[root@server ~]# parted /dev/mapper/mpathj GNU Parted 2.1 Using /dev/mapper/mpathj Welcome to GNU Parted! Type 'help' to view a list of commands. - Once at the parted prompt, create a GPT label on the disk (Note: This will remove any existing partition table and partitions on the device):
(parted) mklabel gpt Warning: The existing disk label on /dev/sdj will be destroyed and all data on this disk will be lost. Do you want to continue? Yes/No? Yes (parted) - The default unit will be GB you can change it to TB if required, I have not changed the default unit to TB. Here default unit is GB
(parted) unit TB - Use the print command to show the size of the disk as reported by parted. We need this later:
(parted) print Model: Linux device-mapper (multipath) (dm) Disk /dev/mapper/mpathj: 3299GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags - Create a primary partition on the device. In this example, the partition will encompass the entire disk (using the size from the step above):
(parted) mkpart primary 0 3299GB - Unlike fdisk, you do not have to write out the partition table changes with parted. Display your new partition and quit.
(parted) print Model: Linux device-mapper (multipath) (dm) Disk /dev/mapper/mpathj: 3299GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 0.02GB 3299GB 3299GB primary (parted) quit Information: You may need to update /etc/fstab.
Again run the command fdisk -l to see and verify the partition which you have created in the above steps.
[root@server ~]# fdisk -l Disk /dev/mapper/mpathi: 1099.5 GB, 1099511627776 bytes 255 heads, 63 sectors/track, 133674 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 16384 bytes / 16777216 bytes Disk identifier: 0xaedc5bdb Device Boot Start End Blocks Id System /dev/mapper/mpathip1 3 133674 1073720340 83 Linux Partition 1 does not start on physical sector boundary. Disk /dev/mapper/mpathj: 3298.5 GB, 3298534883328 bytes 255 heads, 63 sectors/track, 401024 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 16384 bytes / 16777216 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/mapper/mpathjp1 1 267350 2147483647+ ee GPT Partition 1 does not start on physical sector boundary.
As you can see above /dev/mapper/mpathjp1 is the newly created partition and from here we will perform the action on this newly created partition.
Note: If you do not need to create the PV, VG and LV then you can format this partition /dev/mapper/mpathjp1 using the command mkfs and mount it to any mount point.
Create Physical Volume:
Create the Physical Volume using the command pvcreate.
[root@server ~]# pvcreate /dev/mapper/mpathjp1
Physical volume "/dev/mapper/mpathjp1" successfully created
Create Volume Group:
Create the Volume Group using the command vgcreate.
[root@server ~]# vgcreate vgsupload /dev/mapper/mpathjp1
Volume group "vgsupload" successfully created
See the Details of the Volume Group:
See the details of the Volume Group using the command vgdisplay.
[root@server ~]# vgdisplay -v vgsupload
Using volume group(s) on command line.
--- Volume group ---
VG Name vgsupload
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 1
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 1
Act PV 1
VG Size 3.00 TiB
PE Size 4.00 MiB
Total PE 786420
Alloc PE / Size 0 / 0
Free PE / Size 786420 / 3.00 TiB
VG UUID TzD23O-gYN3-e2Il-CI2H-uC1k-AhZQ-hoCg7R
--- Physical volumes ---
PV Name /dev/mapper/mpathjp1
PV UUID edsRG8-5K9L-TIie-Do6N-Q5Vf-4pb6-Idp2Su
PV Status allocatable
Total PE / Free PE 786420 / 786420
Create Logical Volume:
Now create the Logical Volume using the command lvcreate.
[root@server ~]# lvcreate -l 786420 -n lvsupload vgsupload
Logical volume "lvsupload" created.
[root@server ~]# vgdisplay -v vgsupload
Using volume group(s) on command line.
--- Volume group ---
VG Name vgsupload
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 2
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 0
Max PV 0
Cur PV 1
Act PV 1
VG Size 3.00 TiB
PE Size 4.00 MiB
Total PE 786420
Alloc PE / Size 786420 / 3.00 TiB
Free PE / Size 0 / 0
VG UUID TzD23O-gYN3-e2Il-CI2H-uC1k-AhZQ-hoCg7R
--- Logical volume ---
LV Path /dev/vgsupload/lvsupload
LV Name lvsupload
VG Name vgsupload
LV UUID wiecWJ-Sg2W-SNUJ-ucIz-54AI-CEIY-hM3aL4
LV Write Access read/write
LV Creation host, time server, 2017-07-31 12:05:14 +0530
LV Status available
# open 0
LV Size 3.00 TiB
Current LE 786420
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:19
--- Physical volumes ---
PV Name /dev/mapper/mpathjp1
PV UUID edsRG8-5K9L-TIie-Do6N-Q5Vf-4pb6-Idp2Su
PV Status allocatable
Total PE / Free PE 786420 / 0
Format the Volume:
Format the volume in ext4 file format
[root@server ~]# mkfs.ext4 /dev/vgsupload/lvsupload
mke2fs 1.41.12 (17-May-2010)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=4 blocks, Stripe width=4096 blocks
201326592 inodes, 805294080 blocks
40264704 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
24576 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848, 512000000, 550731776, 644972544
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 24 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
Create a mount point and mount:
Create a mount point directory and mount the formatted volume to this directory.
[root@server ~]# mkdir /supload [root@server ~]# mount /dev/vgsupload/lvsupload /supload [root@server ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/sda10 40G 8.6G 29G 23% / tmpfs 48G 153M 48G 1% /dev/shm /dev/mapper/vgsupload-lvsupload 3.0T 72M 2.9T 1% /supload
Note: Above process was performed on RHEL 6.8