Error installing SQL 2008 geo cluster: rule “Cluster shared disk available check” failed

By tom on November 17th, 2009

First a little about our setup, we have what is called a geographically dispersed cluster. This means that the nodes are in different datacenters, each connected to a san in it’s own location and that there is synchronous replication of the LUNs between the sans.

In our case we use Continuous Access (CA) from HP on the san side and on the nodes the client counterpart Cluster Extensions (CLX). You could just as well use PPRC from IBM or the equivalent of your san vendor.

The CLX adds an extra resource in your resource group and your disks (LUNs) have a dependency on this resource:

More info about HP CLX can be found here.

Our OS cluster is fully functional and fail-overs happen without any issues.
However, when trying to install SQL 2008 on it, we get following error by the rule validation step:

After searching for a while and with the help of MS Support, we finally found the problem: disks are not supposed to have any dependencies on them. So for the installation, you have to remove the dependency on the disk for the CLX extension.

After installation, make sure to add the dependency again, otherwise your cluster will not fail-over, because the disk resource will fail.

Note that this happens only on SQL 2008, with SQL 2005 on the same configuration, we never had this problem.

Tom

Storagedata iSCSI SAN solutions

By tom on November 2nd, 2009

I recently bought a Storagedata Xi3160 SAN, which is an affordable iSCSI & Fibre Channel SAN solution. It is a 3U, 16 bay, fully redundant box, which has 4 gigabit ethernet interfaces.

Following versions are available in the iSCSI range:

Model

Connection

HDD

Raw Capacity

SD3160XE-500

4GB iSCSI

SATA II 3GB

8TB (16x 500GB)

SD3160XE-750

4GB iSCSI

SATA II 3GB

12TB (16x 750GB)

SD3160XE-1000

4GB iSCSI

SATA II 3GB

16TB (16x 1000GB)

SD3160XS-146

4GB iSCSI

SAS 15k

2.3TB (16x 147GB)

SD3160XS-300

4GB iSCSI

SAS 15k

4.8TB (16x 300GB)

SD3160XS-400

4GB iSCSI

SAS 15k

6.4TB (16x 400GB)

 

You can extend the box with expansion units (Xt series) to a maximum of 80 disks (or 5 units)

Installation is very easy; if you connect the management NIC to your network, it will register an IP address (provided you have DHCP), which it neatly displays on its so-called LCM (which stands for LCD Control Module) a little display on the front of the box. Now open your webbrowser, type in the IP address and of you go. The interface is very clear and the people of storagedata have implemented wizards you can use if you don’t want do go through a manual setup.

The storagedata SAN solutions offer a great added value for SMEs (Small and Medium sized Enterprise) who need the storage and flexibility, but don’t want the complexity and high-level features iSCSI SAN solutions from the big names offer.

Tom