How to Deploy Microsoft Exchange Server 2010 in a One-Armed Configuration

In a one-armed configuration, the ports that internal Outlook^® clients use to communicate with the Exchange 2010 server using RPC must be preconfigured on both Exchange 2010 and the Barracuda Load Balancer ADC.

If you want to use a single VIP address and single FQDN for your Exchange deployment, you must use a one-armed configuration.

By default, the Exchange 2010 RPC client dynamically selects a port between 1024 and 65535. To allow for a one-armed deployment, configure Exchange to use a static port instead. For more detailed instructions on configuring Exchange 2010 with static ports and hardware Load Balancer ADCs, see the Microsoft TechNet article Load Balancing Requirements of Exchange Protocols.

On each CAS server, complete the following:

1. Configure the static port in the registry. 

   1. Open the Registry Editor by typing regedit in the Start menu. 

   2. Navigate to HKEY_LOCL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeRpc\ParametersSystem.

   3. Add a new DWORD (32-bit) Value, and name it TCP/IP Port. 
      You might need to create the ParametersSystem key prior to adding the DWORD registry value. If prompted, change the Base to Decimal and set the value data to 65500 (or a port of your choice between 1024 and 65535):

      Open

      

      
      

   4. If you have Public Folders in your deployment, repeat these steps to configure the static port in the registry of each server with the mailbox role installed that hosts a Public Folder.

2. Change the port that clients use to connect for directory access. On each CAS server, complete the set of instructions for your Exchange version.

3. Restart the Microsoft Exchange Address Book and the Microsoft Exchange RPC Client Access  services on all the CAS and Mailbox servers that you modified.

4. To verify that your Client Access servers are using ports 65500 and 65501, open a Windows command prompt and run:
   netstat -na
   In the output, look for TCP entries marked as LISTENING with ports 65500 and 65501. An entry is marked as LISTENING for 0.0.0.0:65500 and 0.0.0.0:65501.

On each active Barracuda Load Balancer ADC that handles traffic for CAS services, complete the following steps.

1. Log into the Barracuda Load Balancer ADC, and go to the BASIC > Services page. 

2. Add all of the services listed in Table 1. For each service, add all the real servers in the CAS array. To add a service, click Add Service and enter the values in the corresponding fields. To add a real server, click Add Server and enter the IP address and port for the server.

   
   Table 1. CAS Services

3. If you have the Barracuda Load Balancer ADC 640 and above, you can enable Application Security for Exchange_Web_Services.

   1. For Application Security, select Enable.

   2. For Security Mode, select the Passive mode. It is recommended that you run the service in Passive mode before going active. 

   3. From the Security Policy list, select owa2010. This policy is predefined for all Exchange applications. If you want to edit the policy settings, go to the SECURITY > Security Policies page

   4. You need to modify the default owa2010 policy. Go to the SECURITY > Security Policies page and select the owa2010 security policy. In the Cookie Security section, set Tamper Proof Mode to None.

4. If you require any of the protocols in Table 2, add the service for the protocol.

   
   Table 2. Protocol Services.

For Exchange_Web_Services only, configure health checks for all of its real servers :

1. On the BASIC > Services page, click Edit next to the entry of the real server.

2. Scroll to the Server Monitor section, and enter the values in the corresponding fields.

3. Click Save Changes.

Create content rules for Exchange_Web_Services to maintain persistence for Outlook Web Access, Exchange Control Panel and Exchange Web Services.

1. On the BASIC > Services page, add the rules in Table 3. To add a rule, click Add Content Rule under Exchange_Web_Services in the left pane. Then enter the values in the corresponding fields.
   
   Table 3. Content Rules for Exchange_Web_Services

2. If you are using Outlook Anywhere (HTTPS only, not RPC over HTTPS), you must also add the following content rule for the Offline Address Book.

3. For each of the Content Rules you have configured, you need to add the appropriate Microsoft Exchange server(s). Select each Content Rule and click Add Server and specify your Microsoft Exchange server(s).

4. If SNI is enforced on the Microsoft Exchange server(s), then you need to configure the following options. Go to the BASIC > Services page and click Edit for each affected server.

   1. Change the port on the server to 443.

   2. Navigate to the SSL section and set Server uses SSL to On.

   3. Expand Settings and set Enable SNI to Yes.

On each active Barracuda Load Balancer ADC that handles traffic for Hub Transport Services, configure Hub Transport Services for Exchange 2010.

If your real servers are consolidated with both the CAS and HUB roles installed, add each server for each service that you create. If the Hub Transport role is installed on separate servers (other than those with the CAS role), add only the servers with the Hub role installed. The created services load balance the SMTP traffic to the Hub transport servers for incoming client SMTP connections.

On the BASIC > Services page, add the following SMTP service and, optionally, the SMTP-SSL service. To add a service, click Add Service and enter the values in the corresponding fields. To add a real server, click Add Server and enter the IP address and port for the server.

To simplify access to the Outlook Web Access site for your users, configure a rewrite rule to add /owa to the end of the URL.

1. Go to the TRAFFIC > Web Translations page.

2. From the Service list, select Exchange_Web_Services.

3. In the HTTP Request Rewrite section, add the following rule. Click Add Rule and enter the values in the corresponding fields.

4. Click Save.