Exchange Server 2010 Learning (11) Deploying CAS+HT role High Availability

Exchange Server 2010 uses a role-based management model. Multi-Role Server installation and configuration, we have in the previous article has been introduced. In this case, depending on high availability, we need to deploy the server roles on separate servers and achieve high availability of CAs, HT, and MBX roles. At this point, my plan is to deploy two Cas/hub servers first, and then make the two Cas/hub servers into a CAS Array to provide both client access and Hub transport services. With the CAS array, you can configure the CAS array to become the core server for the Enterprise messaging system, and all mail in and out of the post office must be preceded by a CAS array. The two MBX servers are then deployed, and the two MBX servers are composed of a DAG, which is used to mount the mailbox database, the public folder database is responsible for generating the offline address book, and the mailbox database-level management of address lists, message retention policies, and so on. Microsoft recommends that the Exchange Server 2010 server roles be deployed in the following order: Client access servers, Hub Transport servers, mailbox servers, Edge Transport servers, unified messaging servers. In this case, the Edge Transport server and the Unified Messaging server are not involved, so the cas+ht high availability is described below.

In general, the high availability of CAS and HT uses the Windows NLB feature, which is the most conventional and economical usage. However, NLB is actually problematic because NLB is working on the third tier (the network layer) and does not know if there is a problem with the top-level service. It may also be trying to communicate, so the user experience can be affected. NLB, on the other hand, allocates traffic based on source IP, so if two large networks are communicating. In the NAT network environment 1000 people come over to visit may be one or 10 IP addresses, it is possible to send to a server. So what Microsoft is proposing is a hardware load balancing operation. Because the seventh layer of packet analysis can be performed. After a package comes in, hardware load balancing can be removed, read the corresponding network protocol, for example, whether encryption and so on. Untie and then throw it back to the server, and then pass it to the user after processing. Of course, there are also bad hardware balance, such as expensive, complex configuration. In view of the above, you can use Windows NLB to implement Cas+hu high availability. The topology diagram you use, as shown in the following illustration:

This article describes how to achieve high availability of cas+ht, as well as the high availability of DAG and related configuration, which will be introduced in the following articles. Comb the deployment steps for cas+ht high availability to fully prepare for the following specific actions.

PS: Before you do anything, you need to install the latest service packs or patches for all your computers, and make general settings for your system, network, firewall, and computer name and network settings.

Prepare for AD DS domain environment. Here we prepare two servers, where AD DS is deployed and both servers assume the DNS service, when writing this article, I will only involve DC01.

Prepare to install account. Here we use an Exchange Administrator account.

Installation of a single installation Cas+hub role. This is also a two-server deployment of the Cas+hub role on each server. The appropriate configuration is required on each machine.

Configure Windows NLB.

Create a CAS array.

When we're ready, we'll start.

Step 1:ad the DS domain controller installation. The Exchange server and Active Directory are tightly integrated, and you must do the AD DS deployment work. If you are working in an existing AD DS domain environment, make sure that the DC database, operations master, GC, and so on are in a normal state. The process of the specific ascending and adding fields will not be described in detail here. Refer to the Exchange Server2010 series bis: Triple Role (CAS+HUB+MBX).

Step 2: Prepare to install the account, this account has at least the permissions: Schema Admins, Enterprise Admins,domain Admins, organization Management (this permission is added automatically after the extended schema is completed), All Exchange 2010 installation configuration actions will be performed by this account. As the following illustration shows, this user name is Exadmin and is an administrator of exchange. Note Be sure to operate on the DC.

Step 3: Install the Cas+hub role on a single server. Using the Exadmin user to log on to CASHUB01, run the install Microsoft Office Filter packs as an administrator, this step is simple, just double-click execution, and then install as prompted, as shown in the following illustration: