Clustering , how to start ?

Dear Friends,

i'm using windows 2003 server on both computers

i wanted to practice clustering with sql 200/2005 [two nodes] but it asks for a quorum disk as a shared disk between the two clustered nodes, i didn't know what a quorum disk it, the internet when i searched for says that

a quorum disk should be either a scsi or fiber channel disk, i've never seen a scsi disk, i'll purchase it today, but what i'm confused about is, how will i connect one single scsi disk two two computers/nodes ? i mean does a scsi disk have a long cable to connect to and if yes, then where does the cable fit in on either of the nodes, or is it not physcially shared then if it's logical then how do i configure it.

pls reply soon,

regards, and thanks

Gurjit Singh

Moving this thread to: SQL Server Disaster Recovery and Availability|||

I'd suggest that you start by reading up on the basics of MSCS failover clustering.

http://msdn2.microsoft.com/en-us/library/ms952401.aspx is one place to start, which describes clusters from an application standpoint.

Fundamentally, a cluster consists of 2 or more nodes on a common network, which can all physically access the same storage devices. An application (SQL in this case) is defined to the cluster as a newtork address and name by which that application will be known to the rest of the network, a set of one or more disks which are accessible to all nodes on which the application is allowed to run, and the application itself. When the application starts on a node, that node takes exclusive ownership of the resources defined for it, and starts the application.

This access to the storage is commonly via either SCSI or Fiberchannel. SCSI connections are physically a chain, with one or more "initiators" (the system controller), and one or more devices. There is a terminator on either end of this chain, or "bus".

In a cluster then, a typical layout for a SCSI-based storage system would be to have an extra SCSI adapter on each node, with the chain of disks between the two nodes, and the chain ending at each node. There are other topologies possible, but this is a common one. Note that this bus MUST be separate from the bus on which local system storage (the C: drive, etc.) is located.

Again, this is the 100,000 foot level. There are many many details that need to be gotten right. It's not rocket science, but you do need to pay attention to details. Some reading is definitely in order.