I just want to make sure I understand this correctly...

If you are running only one database (one instance?), and are clustered,
then you must be running in an "active / passive" configuration. There is no
way that both nodes can "share" the single database instance across both
nodes for improved performance (ala Oracle Parallel server or Oracle RAC).

With mulit-instance, where you would have two databases, you could run one
on Node A and one on Node B. Essentially, the databases are separate. But
if one node fails, the other node could operate both instances (with reduced
performance).

Are these statements correct?

Thanks.

Excellent. Thank-you for the speedy reply.

We have a winner. (Yes, the statements are correct).

Each "Instance" is an independent SQL Server and looks like it on the
network. Instances exist independently of each other and can live on any
allowed host node.

The terms "Active/Passive" and its variants are obsolete and no longer
reflect current SQL capabilities.

--
Geoff N. Hiten
Senior Database Administrator
Microsoft SQL Server MVP

[quoted text, click to view]

When you say "instance" do you mean a seperate cluster group and virtual
server? (I might be getting this confused with sql instances)

Someone had a post below about SQL 2000 supports a max 16 instances and 4
nodes. Can someone further explain?

Every new SQL Server clustered instance will require its own group. The
virtual server will be a member of the group, as will its resources.

An instance is simply a SQL Server process. An individual server -
clustered or not - can run up to 16 such instances.

A cluster is a group of machines connected together on which clustered
applications - e.g. SQL Server - can run.

A node is a server within the cluster. Windows 2003 Server EE can support
up to 8 nodes in the cluster, but SQL Server 200 can run only in a cluster
with 1 - 4 nodes.

HTH

--
Tom

----------------------------------------------------
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA
SQL Server MVP
Columnist, SQL Server Professional
Toronto, ON Canada
www.pinpub.com
..
[quoted text, click to view]
When you say "instance" do you mean a seperate cluster group and virtual
server? (I might be getting this confused with sql instances)

Someone had a post below about SQL 2000 supports a max 16 instances and 4
nodes. Can someone further explain?

For a realistic scenario where I set my expectation of no more than one
failed\passive node at any given time, with the 4 node limitation, the best
you can do is a 3 active 1 passive cluster with each node capable of 16
instances\virtual servers?

I'm also a little confused by sql instances still. Would the above scenario
look like this:
sqla\instance1
sqla\instance2...
sqla\instance16

sqlb\instance1
sqlb\instance2...
sqlb\instance16

sqlc\instance1
sqlc\instance2...
sqlc\instance16

Or would it be sqlserver1, sqlserver2, ...sqlserver48?

Sorry I'm a sysadmin and not a sql dba.

It's a total of 16 instances per cluster. Also, the server and instance
name must be unique within the cluster and a virtual server can contain only
one instance. So, you can have:

SQL1\INST1
SQL2\INST2

but not

SQL1\INST1
SQL1\INST2

--
Tom

----------------------------------------------------
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA
SQL Server MVP
Columnist, SQL Server Professional
Toronto, ON Canada
www.pinpub.com
..
[quoted text, click to view]
For a realistic scenario where I set my expectation of no more than one
failed\passive node at any given time, with the 4 node limitation, the best
you can do is a 3 active 1 passive cluster with each node capable of 16
instances\virtual servers?

I'm also a little confused by sql instances still. Would the above scenario
look like this:
sqla\instance1
sqla\instance2...
sqla\instance16

sqlb\instance1
sqlb\instance2...
sqlb\instance16

sqlc\instance1
sqlc\instance2...
sqlc\instance16

Or would it be sqlserver1, sqlserver2, ...sqlserver48?

Sorry I'm a sysadmin and not a sql dba.

So it would be something like:

SQL GROUP1 SQL1 Node1
SQL GROUP2 SQL2 Node1
....
SQL GROUP5 SQL5 Node1

SQL GROUP6 SQL6 Node2
SQL GROUP7 SQL7 Node2
....
SQL GROUP10 SQL10 Node2

SQL GROUP11 SQL11 Node3
SQL GROUP12 SQL12 Node3
....
SQL GROUP16 SQL16 Node3

Yep. That said, I'd go with one instance per node at the most.

--
Tom

----------------------------------------------------
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA
SQL Server MVP
Columnist, SQL Server Professional
Toronto, ON Canada
www.pinpub.com
..
[quoted text, click to view]
So it would be something like:

SQL GROUP1 SQL1 Node1
SQL GROUP2 SQL2 Node1
....
SQL GROUP5 SQL5 Node1

SQL GROUP6 SQL6 Node2
SQL GROUP7 SQL7 Node2
....
SQL GROUP10 SQL10 Node2

SQL GROUP11 SQL11 Node3
SQL GROUP12 SQL12 Node3
....
SQL GROUP16 SQL16 Node3

Thanks very much for clearing this up for me. I understand how Exchange
clusters and knew SQL was different and now I know how.

One last question, is SQL 2005 clustering the same?

Yes and no. SQL Server 2000 EE can go up to 4 nodes. SQL Server 2005 EE
will go to 8, though Std will now support clustering, but only up to 2
nodes. Previously, Std didn't support clustering at all. Also, SQL Server
2005 will have database mirroring, which allows you to provide high
availability on a per-database basis.

--
Tom

----------------------------------------------------
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA
SQL Server MVP
Columnist, SQL Server Professional
Toronto, ON Canada
www.pinpub.com
..
[quoted text, click to view]
Thanks very much for clearing this up for me. I understand how Exchange
clusters and knew SQL was different and now I know how.

One last question, is SQL 2005 clustering the same?

Thanks Tom. I'll need to do some reading on 2005.

[quoted text, click to view]