ASM disk resize/add disk

[Roshan]

Oracle Database 12.2.0
Red Hat Enterprise Linux 7.4

Hi Erman,

fdisk is showing results shown below

fdisk results:

Disk /dev/sdd: 536.9 GB, 536870912000 bytes, 1048576000 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk label type: dos

Disk identifier: 0x36ac345b
 

   Device Boot      Start         End      Blocks   Id  System

/dev/sdd1            2048   524287999   262142976   83  Linux

 

Disk /dev/sdc: 536.9 GB, 536870912000 bytes, 1048576000 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk label type: dos

Disk identifier: 0x4e6e1670

   Device Boot      Start         End      Blocks   Id  System

/dev/sdc1            2048   524287999   262142976   83  Linux

 

Disk /dev/sde: 536.9 GB, 536870912000 bytes, 1048576000 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk label type: dos

Disk identifier: 0x4042930c


   Device Boot      Start         End      Blocks   Id  System

/dev/sde1            2048   524287999   262142976   83  Linux
 

Disk /dev/sdi: 536.9 GB, 536870912000 bytes, 1048576000 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk label type: dos

Disk identifier: 0xad2667fc

     Device Boot      Start         End      Blocks   Id  System

/dev/sdi1            2048   524287999   262142976   83  Linux

Following your comments from http://erman-arslan-s-oracle-forum.2340467.n4.nabble.com/disk-resize-ASM-td7096.html#a7102

I would like to know how:
1. Dismount the associated diskgroup to verify no client database connections are accessing this specific diskgroup

2. How do I resize my physical disk/LUN at OS/hardware level.

 Should I delete partition table '/dev/sdi1' (at OS level) and recreate new partiion using fdisk before firing 'ALTER DISKGROUP RESIZE DISK'; because there is no 'resize' option for fdisk.

3. A LUN is a created from multiple disks or flash disks. How do I choose the size of vdisks (for example /dev/sdi1?)

4. How are vidisks(e.g /dev/sdi) created on hypervisors?

Thanks,

Roshan

[ErmanArslansOracleBlog]

I guess you need to read about OS a little bit more.
/dev/sdi is the disk, /dev/sdi1 is first partition of that disk.
You resize the partitions by recreating them , that s true.

OS Disks (/dev/sd*) are created on Luns.  Luns are not created on disks.
Luns are generally presented by SANs.
You create Luns ons SAN, you map it to your Server, you scan the scsi to see the luns, and once you see the luns, you can create partitions on them (optionally) and you create filesystem on them.. (ext4, ASM etc..) optionally, you mount them.. (for ex mount /dev/sdi1 /data)

How are vidisks(e.g /dev/sdi) created on hypervisors?  -> What do you mean?
If you see /dev/sd* in your OS, then you are ready to go.
Where did this hypervisor thing come from?

Anyways, in case of ASM disk resizing , I gave you the action plan already ->

In an ASM resize operation, you need to do the following only;

1) Backup the database(s) contained inside the associated diskgroup.

2) Shutdown the databases contained inside the associated diskgroup.

3) Dismount the associated diskgroup to verify no client database connections are accessing this specific diskgroup

4)Resize your physical disk/LUN at OS/hardware level.

5)Mount back the diskgroup

6)Resize the ASM disk with ALTER DISKGROUP RESIZE DISK command.

[Roshan]

Hi Erman,

do you advise me this one?

https://www.amazon.com/gp/product/0134277554/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&tag=tutorialinux-20&camp=1789&creative=9325&linkCode=as2&creativeASIN=0134277554&linkId=7b3d8041e639b32baa5d773452df19ee

it seems promising.

Thanks,

Roshan

[ErmanArslansOracleBlog]

This may be a good start.
You need to read and understand the IO Subsystem , and related Linux admin activities.
(adding disk, scanning scsi, partitioning the disks, multipath configuration and etc..)