Add disk or mount point to Oracle RAC

How to add disk to Oracle RAC servers as OCFS2

500GB Disk partition has added from SAN to all four nodes for Database Logical Backup.

How to Detect a New Hard Disk without Rebooting Linux Servers

This command is very intelligent, it will detect new created partition without reboot.

#ls /sys/class/scsi_host/ | while read host ; do echo "- - -" > /sys/class/scsi_host/$host/scan ; done

check is it detected by multipath

[root@rac1 ~]# multipath -ll
mpathb (360014380125db6ff0000700000c50000) dm-26 HP,HSV340 è this is the New partition
size=500G features='0' hwhandler='0' wp=rw
|-+- policy='round-robin 0' prio=1 status=active
| `- 2:0:2:14 sdbb 67:80 active ready running
|-+- policy='round-robin 0' prio=1 status=enabled
| `- 2:0:3:14 sdbc 67:96 active ready running
|-+- policy='round-robin 0' prio=1 status=enabled
| `- 3:0:1:14 sdbe 67:128 active ready running
`-+- policy='round-robin 0' prio=1 status=enabled
 `- 3:0:0:14 sdbd 67:112 active ready running
I removed the other disks print
 [root@rac1 ~]#

Added the entry to multipath.conf file

multipaths {
                 multipath {
                          wwid 360014380125db6ff0000700000c50000
                          alias rman
                          path_grouping_policy group_by_prio
                          path_selector "round-robin 0"
                          failback immediate
                          rr_weight uniform
                           no_path_retry 10
}
 [root@rac1 ~]#

Restart Multipath Service

[root@rac1 ~]# /etc/init.d/multipathd restart
Stopping multipathd daemon: [ OK ]
Starting multipathd daemon: [ OK ]
[root@rac1 ~]#

Check again for new disk detection named rman

[root@rac1 ~]# dmsetup ls | sort
ASMDATA1 (253, 11)
ASMDATA1p1 (253, 22)
Backup-archive (253, 9)
Backup-archivep1 (253, 21)
OCR_DISK1 (253, 4)
OCR_DISK1p1 (253, 14)
OCR_DISK2 (253, 5)
OCR_DISK2p1 (253, 20)
OCR_DISK3 (253, 3)
OCR_DISK3p1 (253, 19)
rman (253, 26)
[root@rac1 ~]#

 Confirmed the disk in mapper

[root@rac1 ~]# ls -l /dev/mapper/
total 0
brw-rw---- 1 root disk 253, 11 Jun 26 06:45 ASMDATA1
brw-rw---- 1 root disk 253, 22 Jun 26 06:45 ASMDATA1p1
brw-rw---- 1 root disk 253, 4 Jun 26 06:45 OCR_DISK1
brw-rw---- 1 root disk 253, 14 Jun 26 06:45 OCR_DISK1p1
brw-rw---- 1 root disk 253, 5 Jun 26 06:45 OCR_DISK2
brw-rw---- 1 root disk 253, 20 Jun 26 06:45 OCR_DISK2p1
brw-rw---- 1 root disk 253, 3 Jun 26 06:45 OCR_DISK3
brw-rw---- 1 root disk 253, 19 Jun 26 06:45 OCR_DISK3p1
brw-rw---- 1 root disk 253, 26 Jul 31 16:42 rman
[root@rac1 ~]#

To mount the new disk you to make a partition of it. Now Creating disk partition

[root@rac1 ~]# fdisk /dev/mapper/rman
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.
The number of cylinders for this disk is set to 65270.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
 (e.g., DOS FDISK, OS/2 FDISK)
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): p
Disk /dev/mapper/rman: 536.8 GB, 536870912000 bytes
255 heads, 63 sectors/track, 65270 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
 Device Boot Start End Blocks Id System
Command (m for help): n
Command action
 e extended
 p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-65270, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-65270, default 65270):
Using default value 65270
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 22: Invalid argument.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
[root@rac1 ~]#

Confirm partition is created

[root@rac1 ~]# fdisk -l /dev/mapper/rman
Disk /dev/mapper/rman: 536.8 GB, 536870912000 bytes
255 heads, 63 sectors/track, 65270 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
 Device Boot Start End Blocks Id System
/dev/mapper/rmanp1 1 65270 524281243+ 83 Linux
[root@rac1 ~]#

 Formatting as ocfs2

[root@rac1 ~]# mkfs.ocfs2 -b 4k -C 32k -L rman /dev/mapper/rmanp1
mkfs.ocfs2 1.6.3
Cluster stack: classic o2cb
Label: rman
Features: sparse backup-super unwritten inline-data strict-journal-super
Block size: 4096 (12 bits)
Cluster size: 32768 (15 bits)
Volume size: 536863965184 (16383788 clusters) (131070304 blocks)
Cluster groups: 508 (tail covers 29996 clusters, rest cover 32256 clusters)
Extent allocator size: 67108864 (16 groups)
Journal size: 268435456
Node slots: 8
Creating bitmaps: done
Initializing superblock: done
Writing system files: done
Writing superblock: done
Writing backup superblock: 5 block(s)
Formatting Journals: done
Growing extent allocator: done
Formatting slot map: done
Formatting quota files: done
Writing lost+found: done
mkfs.ocfs2 successful
[root@rac1 ~]#

 Add the line to fstab and create directory so that it can be auto mount

1st create the mount

[root@rac1 ~]#mkdir /logical-backup
[root@dbsr113 ~]# vi /etc/fstab
And add the below line
/dev/mapper/rmanp1 /logical-backup ocfs2 datavolume,nointr 0 0
[root@rac1 ~]#

To mount the disk read from fstab command is mount -a

[root@rac1 ~]# mount –a

Check and confirm

[root@rac1 ~]# df -h /logical-backup/
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/rmanp1 500G 2.6G 498G 1% /logical-backup
[root@rac1 ~]#

It is done

Configure Backup to New Mount point:

[root@rac1 ~]# mkdir /logical-backup/backup-dg
[root@rac1 ~]# chmod -R 775 /logical-backup/backup-dg/
[root@rac1 ~]# chown -R oracle:oinstall /logical-backup/backup-dg/
[root@rac1 ~]# ls -rlt /logical-backup/
total 0
drwxr-xr-x 2 root root 3896 Jul 31 17:39 lost+found
drwxrwxr-x 2 oracle oinstall 3896 Jul 31 18:04 backup-dg
[root@rac1 ~]#

Create directory backup

SQL> create directory logical as '/logical-backup/backup-dg';
Directory created.
SQL> grant read,write on directory logical to system;
Grant succeeded.
SQL> backup.sh script
expdp system/password parallel=4 dumpfile=Full_database_backup%U.dmp logfile=Full_database_backup.log directory=logical full=y

Add the backup to crontab to run everyday on 10:30PM

[oracle@rac1 script]$ crontab -l
30 22 * * * /home/oracle/script/backup.sh > /backup/datapump/backuplog.txt 2>&1

Shared on the backup directory to SAMBA as well.

[export]
 comment = export
 path = /logical-backup/backup-dg
 public = yes
 writable = yes
 browseable = yes
 inherit permissions = Yes
 printable = no
 guest ok = yes
 directory mask = 0777
 create mask = 0777