Partitioning and formatting a disk in Linux with gdisk and ext4
In this server, /dev/sdb is an unconfigured 36T disk in a RAID-5 configuration:
[jemurray@wuit-s-00229 ~]$ ls -al /dev/sd*
brw-rw----. 1 root disk 8, 0 Mar 24 10:08 /dev/sda
brw-rw----. 1 root disk 8, 1 Mar 24 10:08 /dev/sda1
brw-rw----. 1 root disk 8, 2 Mar 24 10:08 /dev/sda2
brw-rw----. 1 root disk 8, 3 Mar 24 10:08 /dev/sda3
brw-rw----. 1 root disk 8, 4 Mar 24 10:08 /dev/sda4
brw-rw----. 1 root disk 8, 16 Mar 24 10:08 /dev/sdb
Partition /dev/sdb with gdisk:
[jemurray@wuit-s-00229 ~]$ sudo gdisk /dev/sdb
GPT fdisk (gdisk) version 1.0.3
Partition table scan:
MBR: not present
BSD: not present
APM: not present
GPT: not present
Creating new GPT entries.
Examine the disk with the p (print) option:
Command (? for help): p
Disk /dev/sdb: 78134640640 sectors, 36.4 TiB
Model: PERC H740P Mini
Sector size (logical/physical): 512/512 bytes
Disk identifier (GUID): 94A7CF47-5E92-4201-909C-96A4DD15E1C8
Partition table holds up to 128 entries
Main partition table begins at sector 2 and ends at sector 33
First usable sector is 34, last usable sector is 78134640606
Partitions will be aligned on 2048-sector boundaries
Total free space is 78134640573 sectors (36.4 TiB)
Create a new partition with the n (new) option. Keep the default options to use all available space:
Command (? for help): n
Partition number (1-128, default 1): 1
First sector (34-78134640606, default = 2048) or {+-}size{KMGTP}:
Last sector (2048-78134640606, default = 78134640606) or {+-}size{KMGTP}:
Current type is 'Linux filesystem'
Hex code or GUID (L to show codes, Enter = 8300):
Changed type of partition to 'Linux filesystem'
View and validate the newly created partition:
Command (? for help): p
Disk /dev/sdb: 78134640640 sectors, 36.4 TiB
Model: PERC H740P Mini
Sector size (logical/physical): 512/512 bytes
Disk identifier (GUID): 94A7CF47-5E92-4201-909C-96A4DD15E1C8
Partition table holds up to 128 entries
Main partition table begins at sector 2 and ends at sector 33
First usable sector is 34, last usable sector is 78134640606
Partitions will be aligned on 2048-sector boundaries
Total free space is 2014 sectors (1007.0 KiB)
Number Start (sector) End (sector) Size Code Name
1 2048 78134640606 36.4 TiB 8300 Linux filesystem
Write the partition table to disk with the w (write) option:
Command (? for help): w
Final checks complete. About to write GPT data. THIS WILL OVERWRITE EXISTING
PARTITIONS!!
Do you want to proceed? (Y/N): y
OK; writing new GUID partition table (GPT) to /dev/sdb.
The operation has completed successfully.
Partition 1 is created on /dev/sdb:
[jemurray@wuit-s-00229 ~]$ ls -al /dev/sd*
brw-rw----. 1 root disk 8, 0 Mar 24 10:08 /dev/sda
brw-rw----. 1 root disk 8, 1 Mar 24 10:08 /dev/sda1
brw-rw----. 1 root disk 8, 2 Mar 24 10:08 /dev/sda2
brw-rw----. 1 root disk 8, 3 Mar 24 10:08 /dev/sda3
brw-rw----. 1 root disk 8, 4 Mar 24 10:08 /dev/sda4
brw-rw----. 1 root disk 8, 16 Mar 26 15:31 /dev/sdb
brw-rw----. 1 root disk 8, 17 Mar 26 15:31 /dev/sdb1
Create an ext4 partition on /dev/sdb1 with mkfs.ext4:
[jemurray@wuit-s-00229 ~]$ sudo mkfs.ext4 /dev/sdb1
[sudo] password for jemurray:
mke2fs 1.45.6 (20-Mar-2020)
Creating filesystem with 9766829819 4k blocks and 610426880 inodes
Filesystem UUID: 5318a944-1274-4298-b33b-bb0efc7192fe
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, 1934917632,
2560000000, 3855122432, 5804752896
Allocating group tables: done
Writing inode tables: done
Creating journal (262144 blocks): done
Writing superblocks and filesystem accounting information: done
Create a mount point directory for the new disk:
[jemurray@wuit-s-00229 ~]$ sudo mkdir /backup
Mount the disk:
[jemurray@wuit-s-00229 ~]$ sudo mount /dev/sdb1 /backup/
Validate the disk is mounted and its size:
[jemurray@wuit-s-00229 ~]$ df -h /backup/
Filesystem Size Used Avail Use% Mounted on
/dev/sdb1 37T 24K 35T 1% /backup
Mount the disk on reboot, by adding the following line to /etc/fstab:
[jemurray@wuit-s-00229 ~]$ grep backup /etc/fstab
/dev/sdb1 /backup ext4 defaults 1 2
Once the /etc/fstab has the proper device and mount point, attempt to mount the disk with directory name only:
[jemurray@wuit-s-00229 ~]$ sudo mount /backup
One final check to make sure the mount is working as expected:
[jemurray@wuit-s-00229 ~]$ sudo df -h /backup/
Filesystem Size Used Avail Use% Mounted on
/dev/sdb1 37T 24K 35T 1% /backup