dbeutler
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Witness Disk Reserved in Windows 2008 Failover Cluster
I have a Windows 2008 failover cluster which serves a SQL Server 2005 service in a node and disk majority. The witness disk and SQL Server disks(Data, Logs, Indexes, etc.) are all connected through an iSCSI SAN connection. On the inactive node, the witness disk is shown as reserved but is not "online" (which I think is evidenced by the fact that the drive letter is not shown in disk management). Is this normal? Is the witness disk accessible from only one server at a time?
Secondly, each server shows the witness disk properties as Type=basic, Status=Reserved, and Partition Style=GUID Partition Table(GPT). Is that normal and expected?
Thanks
Secondly, each server shows the witness disk properties as Type=basic, Status=Reserved, and Partition Style=GUID Partition Table(GPT). Is that normal and expected?
Thanks
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What I meant to say was, Don't both nodes need access to the Witness Disk at the same time? (BTW-You will be awarded the points)
There are 4 types of quorum configurations for Wiundows Sever 2008:
Node Majority: Each node that is available and in communication can vote. The cluster functions only with a majority of the votes, that is, more than half.
Node and Disk Majority: Each node plus a designated disk in the cluster storage (the disk witness ) can vote, whenever they are available and in communication. The cluster functions only with a majority of the votes, that is, more than half.
Node and File Share Majority: Each node plus a designated file share created by the administrator (the file share witness ) can vote, whenever they are available and in communication. The cluster functions only with a majority of the votes, that is, more than half.
No Majority: Disk Only: The cluster has quorum if one node is available and in communication with a specific disk in the cluster storage. Only the nodes that are also in communication with that disk can join the cluster.
You can tell which Quorum configuration you are using in the "failover cluster management" program. on the server properties. I use "No Majority Disk Only", which is only viewable by the active node (in windows explorer). I'm not sure about the other 3 options. Even though the 2nd node can't acess the drive directly via windows explorer, the servers communicate with each other and verify that the disk will be availbe on a failover event.
All of this is validated at the time you join the clusted with a node.
The best way to see if things are working correctly is to fail the cluster over and see if everything is accessible on the 2nd node. If so, you're fine.
Node Majority: Each node that is available and in communication can vote. The cluster functions only with a majority of the votes, that is, more than half.
Node and Disk Majority: Each node plus a designated disk in the cluster storage (the disk witness ) can vote, whenever they are available and in communication. The cluster functions only with a majority of the votes, that is, more than half.
Node and File Share Majority: Each node plus a designated file share created by the administrator (the file share witness ) can vote, whenever they are available and in communication. The cluster functions only with a majority of the votes, that is, more than half.
No Majority: Disk Only: The cluster has quorum if one node is available and in communication with a specific disk in the cluster storage. Only the nodes that are also in communication with that disk can join the cluster.
You can tell which Quorum configuration you are using in the "failover cluster management" program. on the server properties. I use "No Majority Disk Only", which is only viewable by the active node (in windows explorer). I'm not sure about the other 3 options. Even though the 2nd node can't acess the drive directly via windows explorer, the servers communicate with each other and verify that the disk will be availbe on a failover event.
All of this is validated at the time you join the clusted with a node.
The best way to see if things are working correctly is to fail the cluster over and see if everything is accessible on the 2nd node. If so, you're fine.
ASKER