Cluster lock lun ????

[klemerS]

Hello all.

I am confused. Does lock lun can be part of regular VG ???

If I choose VG which contain active lvm The data will be destroyed ???

From Feb 2007 manual which regard to V1.17 its says:

Choosing Cluster Lock Disks

The following guidelines apply if you are using a lock disk. The cluster

lock disk is configured on an LVM volume group that is physically

connected to all cluster nodes. This volume group may also contain data

that is used by packages.

When you are using dual cluster lock disks, it is required that the default

I/O timeout values are used for the cluster lock physical volumes.

Changing the I/O timeout values for the cluster lock physical volumes

can prevent the nodes in the cluster from detecting a failed lock disk

within the allotted time period which can prevent cluster re-formations

from succeeding. To view the existing IO timeout value, run the following

command:

pvdisplay

The I/O Timeout value should be displayed as “default.” To set the IO

Timeout back to the default value, run the command:

pvchange -t 0
The use of a dual cluster lock is only allowed with certain specific

configurations of hardware. Refer to the discussion in Chapter 3 on “Dual

Cluster Lock.” For instructions on setting up a lock disk, see “Specifying

a Lock Disk” on page 235.


And if you look at Jun Edition regard to V1.18 it says:

Setting Up a Lock LUN

LUN stands for Logical Unit Number. The term can refer to a single

physical disk, but these days is more often used in a SAN (Storage Area

Network) or NAS (Network-Attached Storage) context to denote a virtual

entity derived from one or more physical disks.

Keep the following points in mind when choosing a device for a lock LUN:

• All the cluster nodes must be physically connected to the lock LUN.

• All existing data on the LUN will be destroyed when you configure it as a lock LUN.

This means that if you use an existing lock disk, the existing lock

information will be lost, and if you use a LUN that was previously

used as a lock LUN for a Linux cluster, that lock information will

also be lost.

• A lock LUN cannot also be used in an LVM physical volume or VxVM

or CVM disk group.

• A lock LUN cannot be shared by more than one cluster.

• A lock LUN cannot be used in a dual-lock configuration.

• You do not need to back up the lock LUN data, and in fact there is no

way to do so.

A lock LUN needs only a small amount of storage, about 100 KB.

If you are using a disk array, create the smallest LUN the array will

allow, or, on an HP Integrity server, you can partition a LUN; see

“Creating a Disk Partition on an HP Integrity System”.

• If you are using individual disks, use either a small disk, or a portion

of a disk. On an HP Integrity server, you can partition a disk; see



“Creating a Disk Partition on an HP Integrity System”.

IMPORTANT On HP 9000 systems, there is no means of partitioning a disk or

LUN, so you will need to dedicate an entire small disk or LUN for the

lock LUN. This means that in a mixed cluster containing both

Integrity and HP-PA systems, you must also use an entire disk or

LUN; if you partition the device as described below, the HP-PA nodes

will not be able to see the partitions



Regards

Shalom Klemer

[melvyn burnard · Accepted solution]

>Does lock lun can be part of regular VG ???
No, a Lock Lun is not part of a VG, only a Cluster Lock disk can be part of a regular VG. A Lock Lun is a physical disk that is unuseable for anything else.

>If I choose VG which contain active lvm The data will be destroyed ???
If you use a Cluster Lock Disk, this can be part of a regular shared VG, and no, your data is not destroyed, as the Cluster Lock mechanism uses part of the Bad Block Relocation area on the disk you select in teh VG.


A Lock Lun and a Cluster Lock Disk are two completely different methods of providing cluster arbitration.
The Lock Lun capability for HP-UX only comes with Serviceguard A.11.18 and onwards.
Perhaps if you read the following it may assist you:
http://docs.hp.com/en/B3936-90078/B3936-90078.pdf

[klemerS]

ThanK You !!!!

This Answer my Question.

[klemerS]

I got The Anwser i was Looking For .

Thanks.