How to Partition a 40TB RAID5 Disk on CentOS 6.7 and Create a 36TB Archive Partition

1. View Partitions with fdisk

[root@localhost sysadmin]# fdisk -l
WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted.
Disk /dev/sda: 40000.0 GB, 39999997214720 bytes
... 
/dev/sda1               1      267350  2147483647+  ee  GPT

Note: The filesystem exceeds 16 TB, so the OS automatically converted it to GPT, making fdisk unable to show accurate partition info.

2. Use Parted to View Partition Information

[root@localhost sysadmin]# parted
GNU Parted 2.1
Using /dev/sda
... 
Model: LSI AOC-USAS2LP-H8iR (scsi)
Disk /dev/sda: 40.0TB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Number  Start   End     Size    File system  Name   Flags
1       1049kB  525MB   524MB   ext4
2       525MB   263GB   262GB   ext4
3       263GB   284GB   21.0GB  ext4
4       284GB   288GB   4295MB  linux-swap(v1)

3. Create /archive Partition for Archiving

(parted) mkpart /archive 288G -1
(parted) p
Model: LSI AOC-USAS2LP-H8iR (scsi)
Disk /dev/sda: 40.0TB
... 
5       288GB   40.0TB  39.7TB          /archive
(parted)q

4. Verify New Partition

[root@localhost ~]# fdisk /dev/sda
sda   sda1  sda2  sda3  sda4  sda5 
[root@localhost ~]#

Now the new partition sda5 is visible.

5. Modify /etc/mke2fs.conf

# vim /etc/mke2fs.conf
[fs_types]
    ext3 = {
        features = has_journal
    }
    ext4 = {
        features = has_journal,extent,huge_file,flex_bg,uninit_bg,dir_nlink,extra_isize
        auto_64-bit_support = 1  # add this line
        inode_size = 256
    }

6. Download and Build e2fsprogs

[root@localhost ~]# wget -c http://jaist.dl.sourceforge.net/project/e2fsprogs/e2fsprogs/v1.42.8/e2fsprogs-1.42.13.tar.gz
[root@localhost e2fsprogs-1.42.13]# cd build/
[root@localhost build]# ../configure
... 
[root@localhost build]# make && make install

7. Format the Partition

[root@localhost ~]# mke2fs -O 64bit,has_journal,extents,huge_file,flex_bg,uninit_bg,dir_nlink,extra_isize -i 2048 /dev/sda5
[root@localhost build]# blkid
/dev/sda1: UUID="..." TYPE="ext4"
/dev/sda3: UUID="..." TYPE="ext4"
/dev/sda2: UUID="..." TYPE="ext4"
/dev/sda4: TYPE="swap" UUID="..."
/dev/sda5: UUID="..." TYPE="ext4"

mke2fs options explained:

-b : set block size in bytes

-c: check for bad blocks

-f : set fragment size

-F: force execution

-i : set inode ratio

-N: specify number of inodes

-l : read bad block info from file

-L : set filesystem label

-m : reserve percentage for admin (default 5%)

-M: record last mounted directory

-q: quiet mode

-r: set ext2 version

-R= : set RAID parameters

-S: write only superblock and group descriptors

-v: verbose output

-V: show version

8. Mount the New Partition

[root@localhost build]# df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda3       20G   2.4G   16G  14% /
... 
/dev/sda5       36T   20K   34T   1% /archive
[root@localhost build]# df -i
Filesystem      Inodes IUsed   IFree IUse% Mounted on
/dev/sda5  4293781536    11 4293781525   1% /archive

9. Inspect Filesystem Details with tune2fs

[root@localhost build]# tune2fs -l /dev/sda5
Filesystem volume name: <none>
Filesystem UUID: 3b5789ee-94c2-4296-bd99-5669200d826a
Filesystem features: has_journal ext_attr dir_index filetype needs_recovery extent 64bit flex_bg sparse_super huge_file uninit_bg dir_nlink extra_isize
... (additional tune2fs output omitted for brevity)