Add a new disk in Linux

 Hi All,

Sometimes we might need to a disk to the linux systems. Once storage side allocation done we can follow below steps. Modify path as per your environment and requirement.

[root@oranode1 ~]# lsblk
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda             8:0    0   30G  0 disk
├─sda1          8:1    0  500M  0 part /boot
└─sda2          8:2    0 29.5G  0 part
  ├─rhel-root 253:0    0 26.5G  0 lvm  /
  └─rhel-swap 253:1    0    3G  0 lvm  [SWAP]
sdb             8:16   0   30G  0 disk
sr0            11:0    1 1024M  0 rom
[root@oranode1 ~]# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Command (m for help): n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-62914559, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-62914559, default 62914559):
Using default value 62914559
Partition 1 of type Linux and of size 30 GiB is set
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@oranode1 ~]# lsblk
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda             8:0    0   30G  0 disk
├─sda1          8:1    0  500M  0 part /boot
└─sda2          8:2    0 29.5G  0 part
  ├─rhel-root 253:0    0 26.5G  0 lvm  /
  └─rhel-swap 253:1    0    3G  0 lvm  [SWAP]
sdb             8:16   0   30G  0 disk
└─sdb1          8:17   0   30G  0 part
sr0            11:0    1 1024M  0 rom
[root@oranode1 ~]# lsblk -f
NAME          FSTYPE      LABEL UUID                                   MOUNTPOINT
sda
├─sda1        xfs               05356daf-d70a-4ad8-b3cd-e723f9b11202   /boot
└─sda2        LVM2_member       og6zr5-d0yl-edhh-CFFl-aqL2-gBCA-rqkdsW
  ├─rhel-root xfs               b0c3ea90-e651-40e8-bd27-62b461914edd   /
  └─rhel-swap swap              5a9c4a80-1b23-4065-8a74-33aab0a167e4   [SWAP]
sdb
└─sdb1
sr0
[root@oranode1 ~]# mkfs.xfs /dev/sdb1
meta-data=/dev/sdb1              isize=256    agcount=4, agsize=1966016 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0
data     =                       bsize=4096   blocks=7864064, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=0
log      =internal log           bsize=4096   blocks=3839, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

[root@oranode1 u01]# mkdir /u02

[root@oranode1 u01]# mount /dev/sdb1 /u02

[root@oranode1 u01]# lsblk
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda             8:0    0   30G  0 disk
├─sda1          8:1    0  500M  0 part /boot
└─sda2          8:2    0 29.5G  0 part
  ├─rhel-root 253:0    0 26.5G  0 lvm  /
  └─rhel-swap 253:1    0    3G  0 lvm  [SWAP]
sdb             8:16   0   30G  0 disk
└─sdb1          8:17   0   30G  0 part /u02
sr0            11:0    1 1024M  0 rom

[root@oranode1 u01]# df -h
Filesystem             Size  Used Avail Use% Mounted on
/dev/mapper/rhel-root   27G   15G   12G  57% /
devtmpfs               697M     0  697M   0% /dev
tmpfs                  706M   96K  706M   1% /dev/shm
tmpfs                  706M  9.0M  697M   2% /run
tmpfs                  706M     0  706M   0% /sys/fs/cgroup
/dev/sda1              497M  122M  376M  25% /boot
/dev/sdb1               30G   33M   30G   1% /u02

Add an entry like below in  /etc/fstab

/dev/sdb1 /u02 xfs     defaults        0 0

We are done!!!!

Thanks,

PostgreSQL - How to handle "duplicate key value violates unique constraint"

One of application was not coming up and during DB connection it was showing:

duplicate key value violates unique constraint"

To reset the Primary Key performed below steps and application started successfully.