Installing a Two Node Exchange Server 2007 Single Copy Cluster (SCC) in a Virtual Server Test Environment – Part 1: Preparing the virtual environment
July 5, 2011 Leave a comment
Exchange Server 2007 supports two types of cluster setups – Cluster Continuous Replication (CCR) and Single Copy Clusters (SCC). In this three part article series we’ll install and configure a two node active/passive Single Copy Cluster in a Virtual Server 2005 R2 test environment. An Exchange 2007 Single Copy Cluster is very similar to a Exchange Server 2003 active/passive cluster, although a few changes and improvements have been introduced in Exchange Server 2007. A Single Copy Cluster is basically a clustered mailbox server, which consists of two or more servers (known as nodes) which shares the same storage (typically for databases and log files). The shared storage subsystem is typically an SAN or a NAS.
Exchange Server 2007 doesn’t support active/active clusters like is the case with previous Exchange versions, only active/passive.
An Exchange 2007 Single Copy Cluster (SCC) provides high availability of server resources, as one node takes over should the active node for some reason fail. In addition you can apply Hot Fixes, Service Packs etc. to the nodes without having any downtime of your mission-critical messaging environment at all. But bear in mind that a single copy cluster is susceptible to failure of the shared storage subsystem. This means that no matter how many nodes are part of your cluster you’ll always have a single point of failure when using this type of cluster opposite cluster continuous replication (CCR), which provides storage group fail-over via the new log file shipping and reply technology (I’ll cover CCR in another article series here on MSExchange.org).
Since most of you don’t have the necessary hardware for a cluster, before you decide you want to deploy a cluster in your environment, I thought it would be a good idea to show you how to install a single copy cluster in a virtual server 2005 R2 environment.
Pretty much all of the steps in the section where we install a clustered Exchange 2007 Mailbox server can also be used when installing the cluster on “real” hardware.
In order to follow the steps throughout this article series, you need the following:
One physical machine running Virtual Server 2005 R2. Since this product is free to download from the Microsoft web site, this shouldn’t be a problem.
A Windows 2003 Active Directory forest with at least one Domain Controller (raised to 2000 or 2003 forest functional level).
At least one existing Exchange 2007 Hub Transport/Client Access Server already installed in the above forest
Two virtual guests running Windows 2003 R2 or Windows 2003 SP1 Enterprise Edition with at least 512MB RAM and two virtual NICs each – one for the Public network and one for the Private network. This means you need to create an additional virtual network on the virtual host server, None (Guest Only) is sufficient for this network.
In order to install Exchange 2007 Single Copy Cluster, you need to install the cluster HotFix mentioned in MS KB article 898790 (at the time of this writing you need to contact Microsoft Product Support Services in order to acquire this HotFix)
Since Exchange Server 2007 Beta 2 isn’t supported in a production environment, unless you’re participating in the Rapid Deployment Program (RDP) or Technology Adopter Program (TAP), you should install the Single Copy Cluster in a test domain.
Configuring the Network Settings for the Cluster nodes
When you have started the two virtual guests that are to be the nodes in the cluster, start by naming the machines E2K7Node1 and E2K7Node2 or whatever naming scheme you want to use (these names have nothing to do with the Exchange server name which your clients will connect to). Now name the two network connections Public and Private for the external and the internal network respectively (remember to do so on both nodes).
Figure 1: Network Connections
Click Advanced > Advanced Settings, if it’s not already the case make sure Public is listed first on the binding order list, then Private and lastly Remote Access Connections.
Figure 2: Binding order
Also make sure you untick File and Printer Sharing for Microsoft Networks for the Private network connection.
Figure 3: Disabling File and Printer Sharing for Microsoft Networks
Configure the Public network with the respective network settings you use in your test environment.
Figure 4: Configuring the Public network
Configure the Private network with an IP address and a subnet mask. Nothing else is required since this network is only used for communication (heartbeats) between the nodes in the cluster.
Figure 5: Configuring the Private network
Now click Advanced then select the DNS tab. Here you should untick both Register this connection’s addresses in DNS and Use this connection’s DNS suffix.
Figure 6: Configuring DNS settings for the Private network
Click the WINS tab. Untick Enable LMHOSTS lookup and select Disable NetBIOS over TCP/IP.
Figure 7: Configuring WINS settings for the Private network
Click OK three times and close the network connections window.
Now add both Windows 2003 Servers as member servers in your Active Directory test domain.
Creating the Shared Quorum Cluster Disk
As those of you with cluster experience are aware of, a Windows cluster requires a quorum cluster disk. This quorum disk is used to store cluster configuration database checkpoints and log files which helps manage the cluster as well as maintain consistency. Since we’re dealing with a virtual environment we need to create this disk in the Virtual Server 2005 R2 web console. This is done by opening the Virtual Server Manager then clicking Create > Fixed Size Virtual Hard Disk under Virtual Disks.
Figure 8: Creating a fixed size virtual hard disk
Place the virtual hard disk file (.VHD) in the folder containing your two virtual Windows 2003 Servers, then set the size to 500MB (or less if you’re low on disk space). Then click Create.
Figure 9: Specifying the virtual hard disk file name and size
We now need to add the virtual quorum disk to each of the two virtual Windows 2003 Servers. Let’s add it to E2K7SCCNode1 first, we do this by clicking Master Status > E2K7SCCNode1 > Edit Configuration. Since this disk needs to be shared between the nodes, we need to click SCSI Adapters then Add SCSI Adapter. Under the new SCSI adapter tick Share SCSI Bus for Clustering then set the SCSI adapter ID to 6 (or whatever is unused in your environment).
Figure 10: Adding an additional shared SCSI adapter
We now need to make the new disk visible on each node, therefore click Hard disks > Add disk then select SCSI 1 ID 0 in the Attachment drop-down menu. Finally specify the path to the virtual Quorum disk, which in this example is O:\virtual\scc\shared disks\quorum.vhd.
Figure 11: Adding an additional virtual hard disk
Remember to add the SCSI adapter as well as the quorum disk to both servers.
We now need to partition the Quorum disk in the Disk Management console on E2K7SCCNode1, therefore start the virtual machine > logon using a domain admin account > click Start > Run and type Compmgmt.msc. Under Storage click Disk Management. Click Next three times in the appearing Initialize and Convert Disk Wizard, then click Finish.
The detected disk now needs to be partitioned, in order to do so right-click the unallocated space then select new partition.
Figure 12: Partitioning the quorum disk
Click Next three times and select the drive letter Q (for quorum), then click Next again. Use NTFS as the file system type and type Quorum in the Volume label field. To speed up the formatting process it’s a good idea to tick Perform a quick format.
Figure 13: Specifying how the new partition should be formatted
Now turn off E2K7SCCNode1 then turn on E2K7SCCNode2 and log on to the server with a domain admin account. Again click Start > Run and type Compmgmt.msc. Under Storage click Disk Management. Mark the Quorum disk (disk 1) active and assign it the drive letter Q. Now verify you can access the Q: drive from Windows Explorer, also try to create a test file on each server and make sure you can see it both ways.
Figure 14: Allocate the new partition to the drive letter Q
Since we need at least one more shared disk (for the shared Exchange databases and log files), you need to go through the above steps for each virtual disk you add to the SCSI 1 adapter. Nope I won’t detail the steps for adding additional disks to the cluster nodes, as the process is more or less identical.
Okay we have reached the end of part one. In part two (which will be released soon here on MSExchange.org), we’ll go through creating and configuring the Windows 2003 Cluster.