lock disk?

[Mauro Cimino_2]

I havn't understood how the lock disk work. I saw that it is mandatory in a 2 node cluster, but how does it work?

[John Palmer]

Suggest you have a look at the Serviceguard documentation at:
http://www.docs.hp.com/hpux/onlinedocs/B3936-90065/B3936-90065.html
and look in the index for 'lock'

Regards,
John

[T G Manikandan]

Is this what you are looking for

http://www2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000062686663

[melvyn burnard]

A lock disc is nothing more than a tie-breaker in the event that there is an EXACT 50% quorum upon cluster reformation.
It is not used at any other time, and if it is not available when needed, then unpredictable results can occur.
For the newer versions of ServiceGuard you can use the Quorum Server software instead of a lock disc.

[Ravi_8]

Hi,


In MC/ServiceGuard, a cluster-lock disk is employed to resolve cluster reformations in the event that an even split between hosts
occurs, where heartbeat transmission ceases.
MC/ServiceGuard relies on a periodic heartbeat transmission between hosts to determine if a member of the cluster has ceased to function. Should the heartbeat fail to transmit, a cluster reformation is initiated to insure the suspected dead hosts packages are adopted.
A cluster reformation may involve the cluster-lock disk when there is an even split between hosts losing the heartbeat, in the case of a LAN outage. (See NOTE). An even LAN split failure would occur when a LAN failure occurs in the middle of two or 4 hosts. When this occurs, there is a need to negotiate which set of hosts gets to form a new cluster and assume control of the other hosts packages. The negotiation takes the form of a race to the
cluster-lock disk.