Tuesday, March 27, 2012

Downside of SQL Server Clusters

Howdy,

We're interested in putting a SQL 2000 cluster together and want to hear from people who have run SQL Server clusters :

(1) Just how reliable are they in the real world?

(2) Which bits break ( i.e. hardware or OS or SQL Server )

(3) What configuration would you suggest and why?

Any help much appreciated

SG.After we had a hardware failure on our old SQL box, we've also been thinking of doing this.

I would think it would be more reliable with failover protection. We've looked into getting two Dell PE 1750's and the EMC AX100 running an Active/Passive Cluster. SQL 2000 Enterprise/Windows 2003 Enterprise.|||Single-instance (formerly known as Active/Passive) will give you what you're looking for. Check HCL thoroughly to make sure you're not introducing problems while implementing the solution.|||Thanks for that - what I'm after is peoples experiences with thier clusters.

What breaks & why...which part is unreliable...that sort of thing.

Thanks.|||Hardware-related problems are the biggest in clustering. Other than that it's very stable and reliable, even for high volume OLTP systems (NASDAQ is running it, as you might know)|||We're running Windows 2003 cluster, with three instances, active-active-active. We migrated over from a single-instance install active-passive and find our new cluster much more robust, although not without problems:

Installation:

Can be a pain, but with all of the equipment in place, it's not too bad. We moved from a connected shared SCSI array to a SAN which involved a lot of preparation (thanks to Dell it went smoothly).

Installation of the cluster between nodes was a breeze, on either Windows 2000 or 2003.

SQL 2000 Advanced Server was/is our main problem. A lot of Knowledge Base article lookups were required to nail it down:

1. On Windows 2000 Enterprise, SQL 2000 Advanced install was uneventful until you get to MSDTC. Be careful to install MSDTC on each node ONE AT A TIME. Don't do this simultaneously. Once MSDTC is up and running, leave it alone.

2. On Windows 2003 Enterprise, it will complain that SQL 2000 Advanced can't be installed unless it has SP2 built-in, which does not exist. A Knowledge Base article was found where you have to run a resourcekit utility to work around the problem. Looking through the setup logs, as suggested by an official MS webinar "Troubleshooting SQL 2000 installation on Windows 2003 Cluster" helped but not much.

3. MSDTC on Windows 2003 Cluster is a pain. I still can't get it to work and my maintenance plans are broken. Installing MSDTC is totally different on 2003 Cluster vs. 2000 Cluster. Following the Knowledge Base instructions on installing MSDTC, my backups and tlogs still fail and MSDTC seems to run on only one instance, not shared among all three as it's supposed to be.|||3. MSDTC on Windows 2003 Cluster is a pain. I still can't get it to work and my maintenance plans are broken. Installing MSDTC is totally different on 2003 Cluster vs. 2000 Cluster. Following the Knowledge Base instructions on installing MSDTC, my backups and tlogs still fail and MSDTC seems to run on only one instance, not shared among all three as it's supposed to be.

A Knowledge-Base article Hotfix emailed to me seems to work and my first major backup was successful. Now waiting until midnight to apply the hotfix to the rest of the servers to see if my nightly backups and scheduled transaction log backups work...

I just wish this hotfix solution was available from the start, instead of having us waste a couple of weeks of troubleshooting.|||can you post some links to these particular articles because we are setting up a active/passive sql cluster using windows 2003

Thanks|||can you post some links to these particular articles because we are setting up a active/passive sql cluster using windows 2003

Thanks

No problem, Ebola:

Problem Installing named instance of SQL 2000 on 2003 Cluster (http://support.microsoft.com/default.aspx?scid=kb;en-us;815431)
I forgot to mention our problem with installing SQL 2000 instances, but this link gets around both issues regarding SP2 and installing instances...

MSDTC - How To Install on a Windows 2003 Cluster (http://support.microsoft.com/default.aspx?scid=kb;en-us;301600)

DB Maintenance Failures - MSDTC Hotfix (http://support.microsoft.com/default.aspx?scid=kb;en-us;827452)
The hotfix did the trick after running it on all three servers, by the way. All backups are working. The only trick about the hotfix was to delete the MSDTC Resource and recreate it if you already tried creating one before the hotfix.

Hope this helps and let me know if you run into any issues outside of these.|||Not to bring back a thread from the dead but today I got our Active/Passive SQL cluster up and running. Thanks to SunStroke for the DTC link.

I found it worked better to install SQL 2000 on one node at a time.

If anyone is wondering here is a hardware list. It was a relatively smooth install.

Node 1
Dell PE 1850
Windows 2003 Enterprise
dual xeon 3.0 ghz
3 GB ram
Raid 1 PERC
Qlogic HBA (Fibre Channel)
Dual port Intel 1 Gb Network

Node 2
Dell PE 1850
Windows 2003 Enterprise
dual xeon 3.0 ghz
3 GB ram
Raid 1 PERC
Qlogic HBA (Fibre Channel)
Dual port Intel 1 Gb Network

Dell EMC AX100 DP
4 active 250 GB Drives in RAID, 1 spare.

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