Clustering of Mailbox Servers based on CCR Clustering (Cluster Continuous Replication)
What is CCR Clustering?
Cluster Continuous Replication or a CCR Cluster is one of the many new features of Microsoft Exchange 2007. It is a combination of traditional active/passive based Windows Clustering found in Windows 2003 Server environment with a capability of combining Exchange 2007 log file shipping and replay features.
A “CCR Cluster” as generally referred to is basically set of mailbox servers clustered in a way that each Mailbox server maintains its own copy of mailbox database attached exclusively to it. These server-maintained, databases replicate with each other and work in “Active / Passive” mode.
A CCR cluster presents high availability of mailbox server and database by keeping 2 copies of data. In order to form a CCR cluster the databases can be stored on 2 different SANs or they can reside in the internal storages of Mailbox servers.
Deployment Considerations
There are certain requirements for establishing a CCR Cluster.
- A Windows 2003 Active Directory forest (functional level raised to 2000 or 2003)
- Two Windows 2003 Server Enterprise Edition Servers (SP1 is a minimum requirement however R2 is a good choice)
- One Windows File share Witness (Microsoft recommends to use an Exchange 2007 Hub Transport Server for this in same Exchange 2007 organization)
Installation
There are few pre-requisites to be followed for installation of CCR cluster.
Who can install a CCR Cluster?
A user installing cluster must be member of following groups
- Domain Administrators
- Enterprise Administrators
- Local Administrator
What are the Hardware Requirements?
Depending on hardware availability and utilization requirements Mailbox server is installed on a separate physical or virtual machine.
Mailbox Server does not require communication to outside world through internet so generally it is not placed in DMZ in a corporate network.
In case Active Directory is running on 32bit platform, there should be a consist ratio of 1:4 for Active Directory processor cores to Exchange 2007 Mailbox processor cores.
If Active Directory is running on the x64 platform (64-bit), the recommended ratio is 1:8
Mailbox role requires 2GB of RAM for its own processing
For every mailbox additional 5MB of RAM is also required, e.g. for 100 mailboxes a total of 2GB+500MB RAM will be required
1.2 GB free space available on installation drive and 200 MB free space on system drive
For Hub server and EDGE server queues a minimum of 4 GB disk space is required in addition.
File system must be formatted as NTFS on all drives
A heart beat cable for cluster replication is also required.
What are the Software Requirements?
Minimum requirement for Domain Functional Level is Windows 2000 (Native)
Operating system must be Windows Server 2003 64bit with SP1 or higher
Operating system must be fully patched and antivirus installed with latest definition updates before you perform any installation activity.
There are some basic windows components that must be installed on the server before we begin installation of any exchange server role. These components are
Once all the hardware is configured to use and powered ON with basic OS and antivirus installations and updates etc, we can now proceed with the starting of installation procedure.
Installation Procedure for Clustered Mailbox Role
Installation of a clustered mailbox role involves 2 main stages.
In stage 1 we install and configure OS level Windows “Active/Passive” clustering.
In stage 2 we install and configure application level “Exchange 2007 Mailbox” clustering
Installing and Configuring Cluster Pre-Requisites
In order to establish a cluster first thing you need is a very stable local area network.
You must have 2 IPs of same subnet as you AD, DNS and other exchange servers. These two IPs will be used for 2 exchange mailbox physical nodes
1 IP of same range is required for cluster management
1 IP of same range is required for exchange server’s virtual node
You need 2 IPs of a private range which are not used on your LAN environment by any other computer or application. These 2 IPs will communicate to each other for cluster replication through heart beat cable.
In order to make it more clearly, we mention here the IPs used for this article and environment
Let’s say we use following IPs (same subnet as other server roles)
Mailbox Node 1(Physical/NIC1) 172.16.1.11
Mailbox Node2(Physical/NIC1) 172.16.1.12
Mailbox Cluster(Virtual) 172.16.1.13
Windows Cluster (for Management) 172.16.1.14
Now in order to establish cluster replication between two nodes we use a different scheme which is not used elsewhere in our environment
Mailbox Node1 (Physical/NIC2) 10.1.1.1
Mailbox Node2 (Physical/NIC2) 10.1.1.2
Create a shared folder on a third server within same environment and subnet as “Majority Node Share” (Microsoft recommends it to be placed on Hub Server however it can be placed on any stable physical server)
Create a new user in active directory and grant full access to the user account for this majority node share For our environment we have created a user named clsAdmin
It is important to create a separate user for cluster administration. This saves a lot of hassle in future
Now in order to configure the network setting for cluster, go to
Start> Control Panel
Open“Network Connections”
From the menu bar on top go to “Advanced” and select“Advanced Settings”
In the advanced settings, keep LAN connection on highest priority and Cluster on lower priority
By selecting the cluster connection, Uncheck“File and Printer Sharing for Microsoft Networks” and click “Ok”
Now go to the connection properties of NIC reserved for cluster
Select Internet Protocol (TCP/IP) properties
Go to DNS tab and uncheck this option
“Register this connection’s address in DNS”
From “WINS” tab make sure
“Enable LMHOSTS Lookup” is unchecked
DisableNETBIOS overTCP/IP radio button is selected
Click“Ok”
Now go to
Start > All Programs > Administrative Tools > Cluster Administrator
Cluster Administration console will open up for the first time
From the drop down Action menu select “Create new cluster”
Click“Ok”
Click “Next” on wizard
Domain name is selected by default however for multiple domains scenario you will have to select the desired domain name from the list
Give a descriptive name to cluster as per your organization’s naming convention
Click “Next”
Enter computer name by browsing through the button next to “Computer name” field
Click “Next”
Cluster configuration will start
Click “Next”
Enter IP address we reserved for cluster administration
Click “Next”
Provide credentials of cluster administrator account we created earlier for this purpose
Click “Next”
In the next windows before proceeding any further click on “Quorum” button to configure quorum settings
Select“Majority Node Set” from the drop down list and click “OK”
Click“Next”
After a re-analysis cluster creation will be done.
It is normal to have some warnings while creating 1st node of cluster so you can ignore them if task accomplishes in the end
Click “Finish” to close wizard after task completion
Now you will observe mail box node is present in the cluster administration console
Click action button again to do remaining configuration
Click“Open connection to cluster” from drop down menu and click “Ok”
Select “Add nodes to cluster”
From the Add Nodes Wizard click“Next”
Click Browse button to select second node computer
Click“Add” to add this computer in list
Click“Next”
When cluster completion task is completed click“Next”
Provide credentials for the cluster administration account and click “Next”
After reviewing summary of cluster settings, click “Next”
Re-analysis and task completion of cluster will accomplish in a short while
Click “Next”
Click “Finish”
Now you can observe two cluster nodes added in cluster administration console automatically
In order to register the “Majority Node Share” with cluster go to command prompt and type this command
cluster res “Majority Node Set” /priv MNSFileShare=\\AD\MNS
In this command AD is name of the server and MNS is name of folder shared as “Majority Node Set”
Now type this command to move cluster group between two nodes
cluster group “Cluster Group” /move
Successful move will ensure that cluster is working fine
Properties of Majority Node Set can be viewed by this command
cluster res “Majority Node Set” /priv
Installing Exchange Server Pre-Requisites
For the installation of Internet Information Services (IIS) follow these steps,
Go to Start Menu > Control Panel and click “Add or Remove Programs”
On the Add or Remove Programs screen click last tab on the left side “Add/Remove Windows Components”
A wizard will start to assist the installation procedure.
On the Windows Components Wizard screen select “Application Server” and click “Next”
The installation will begin for IIS services.
Incase installer process asks for additional files located on any CD of Windows XP or Windows7, provide correct path of the directory or CD location by clicking browse button shown on your pop up screen
After providing the correct path click “OK” to continue installation
The installation will start for IIS
Once installation is completed click “Finish” to exit
Now close “Add or Remove Programs”
In order to install first we have to get a re-distributable installation package of dot Net Framework 2.0 from Microsoft’s website.
You can download dot NET Framework 2.0 from this URL
http://www.microsoft.com/en-us/download/details.aspx?id=6523
After downloading the executable file on your desktop, double click on this file to initiate the installation procedure
On first screen it will ask for user’s consent to install dot Net Framework 2.0
Click “I have read and ACCEPT the terms of the license agreement”
You can leave the blue highlighted checkbox blank if you want as this is an optional one.
Then click “Install”
The Installation will start for dot NET framework 2.0
After the Installation is complete click “Exit” button to complete the installation process
Microsoft Management Console (MMC) 3.0 generally comes pre-installed with X64bit systems however it can be downloaded from this URL if required
http://www.microsoft.com/en-us/download/details.aspx?id=12709
Windows Power Shell 1.0 can be downloaded from this URL
http://www.microsoft.com/en-us/download/details.aspx?id=11892
After downloading the executable file, double click on file to run the setup process
On the first screen of installation wizard, click “Next” to start installation of Windows Power Shell 1.0
On the next screen select “I Agree” radio button and click “Next”
The Installation will start
Once installation is completed click “Finish”
After installing all pre-requisites, restart the server for changes to take effect
Now that systems have been installed and configured with all clustering and application pre-requisites we shall start with Operating System Level Clustering
Installing Windows 2003 based Clustering
Installation of Exchange Server 2007 (Mailbox Role)
Active Node
On the machine proposed for active mailbox node,
Go to the installation source in DVD or where you have copied it after downloading.
Select “SETUP.EXE” which is generally found on the root of installation folder.
Double click this executable file to initiate the setup process.
Exchange Server 2007 window will open up.
Here you can see that initial 3 steps are grayed because we have already installed pre-requisites and exchange setup has detected this too. If any of the first 3 options are not grey please review your installation steps and repeat the installation procedure for not installed component.
Now move to the first available option i.e. Step 4: Install Microsoft Exchange 2007 SP1 click this option to begin installation.
On the introduction screen, setup will give you a brief description of the product.
Click “Next” to proceed.
On the license agreement screen you can read the license agreement, once satisfied with the documentation you can now click “I accept the terms in the license agreement” and click “Next” to proceed
Next screen will show Error Reporting feature for exchange. This feature can be disabled with no effect on installation however to get a feedback from user end, Microsoft recommends that you click “Yes” to proceed.
On the “Installation Type” screen you have two options. Either you can go for typical installation which can install multiple roles on same box or you can select an individual role for this specific machine.
As scope of this document is to install Client Access Server only so we will click on second option
“Custom Exchange Server Installation”
After choosing the installation type click on “Browse” button to mention the installation path where you plan to put all the installation. In this example we are choosing a folder created for CAS installation on C drive.
Click “Next”
Server Role Selection screen will appear. Here you have choices to select any one or more server roles.
Select “Active Clustered Mailbox Role” and click “Next”
Type name of organization and click “Next”
Select CCR type of cluster; provide clustered mailbox name and location
Click “Next”
Provide IP which we reserved for Clustered Application Node and click “Next”
Click “Next”
After readiness check is complete click “Install”
Click“Finish” upon completion of exchange 2007 installation
Click“Ok” after reading the message
Now click“Close”
Click“Yes” to confirm Exit and restart the system for changes to take effect
Passive Node
On the machine proposed for passive mailbox node,
Go to the installation source in DVD or where you have copied it after downloading.
Select “SETUP.EXE” which is generally found on the root of installation folder.
Double click this executable file to initiate the setup process.
Exchange Server 2007 window will open up.
Here you can see that initial 3 steps are grayed because we have already installed pre-requisites and exchange setup has detected this too. If any of the first 3 options are not grey please review your installation steps and repeat the installation procedure for not installed component.
Now move to the first available option i.e. Step 4: Install Microsoft Exchange 2007 SP1 click this option to begin installation.
On the introduction screen, setup will give you a brief description of the product.
Click “Next” to proceed.
On the license agreement screen you can read the license agreement, once satisfied with the documentation you can now click “I accept the terms in the license agreement” and click “Next” to proceed
Next screen will show Error Reporting feature for exchange. This feature can be disabled with no effect on installation however to get a feedback from user end, Microsoft recommends that you click “Yes” to proceed.
On the “Installation Type” screen you have two options. Either you can go for typical installation which can install multiple roles on same box or you can select an individual role for this specific machine.
As scope of this document is to install Client Access Server only so we will click on second option
“Custom Exchange Server Installation”
After choosing the installation type click on “Browse” button to mention the installation path where you plan to put all the installation. In this example we are choosing a folder created for CAS installation on C drive.
Click “Next”
Server Role Selection screen will appear. Here you have choices to select any one or more server roles.
Select “Passive Clustered Mailbox Role” and click “Next”
On completion of readiness check click “Install”
As this is the passive node installation, most of the settings have already been determined in active node and are not needed here.
Click “Finish”
Click “Ok” after reading the warning
Click “Close” to exit wizard
Click“Yes” to confirm Exit and restart the system for changes to take effect
Now that clustered mailbox has been installed you can verify by opening cluster administrator console on any node,
Go to “Resources” tab and all server and exchange resources should be available there.
Go to “Groups”
In the right side pane right click “Cluster Group” and from the action menu click “Move Group”
Owner of cluster group will change from node 1 to node 2
Now right click “MBX” and from the action menu click “Move Group”
Owner of MBX will also be changed to node2 confirming proper functionality of clustered mailbox.
Under the “Resources” tab all resources can now be seen under the ownership of second node
Conclusion
Exchange 2007 mailbox clustering has been configured successfully and can be verified by moving resources between two nodes of CCR cluster.
Now exchange mailbox role is high available for smooth working. If one node goes down due to any network, application or hardware issue resources will shift to second node automatically.
