Re: 2-node LAVC cluster with quorum disk - network disappears - which node CLUEXITs ?
From: Michael Moroney (moroney_at_world.std.spaamtrap.com)
Date: 02/25/04
- Next message: briggs_at_encompasserve.org: "Re: DCL help"
- Previous message: Nomen Nescio: "J F kooks out on Nader, Bush, et al"
- In reply to: Roy Omond: "2-node LAVC cluster with quorum disk - network disappears - which node CLUEXITs ?"
- Next in thread: Chris Moore: "Re: 2-node LAVC cluster with quorum disk - network disappears - which node CLUEXITs ?"
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Date: Wed, 25 Feb 2004 17:24:51 +0000 (UTC)
Roy Omond <Roy@Omond.net> writes:
>Scenario:
>NODE1 <------ Ethernet ------> NODE2
> + +
> | |
> | |
> +----- Shared SCSI bus --------+
> |
> |
> | Disks including quorum disk
>Both nodes have 1 vote, as does the quorum disk,
>expected votes set to 3, quorum therefore is 2.
>Ethernet gets, ahem, "disconnected".
>One of the nodes voluntarily exits the cluster.
>Question: which one ? And why ?
There is a formula that if a cluster gets partitioned, the portion with
the most votes remains up, and if there is a tie, the portion with the
most nodes remains up. That doesn't answer your question (I believe the
official answer is 'it's random'), but if you are trying to ensure that a
certain node survives in that situation, you really don't have two equal
nodes. If that's what you're trying to do, split the votes unequally
(say, give 11 votes to the node you want to survive, 10 to the other and
10 to the quorum disk. Expected votes will be 31, quorum will be 16, and
your cluster will work as before (you can lose any one, but not any two
of the two nodes and quorum disk) except lose the net connection the
node with 11 votes will be the one that stays up.
-- -Mike
- Next message: briggs_at_encompasserve.org: "Re: DCL help"
- Previous message: Nomen Nescio: "J F kooks out on Nader, Bush, et al"
- In reply to: Roy Omond: "2-node LAVC cluster with quorum disk - network disappears - which node CLUEXITs ?"
- Next in thread: Chris Moore: "Re: 2-node LAVC cluster with quorum disk - network disappears - which node CLUEXITs ?"
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Relevant Pages
|
