Since Exchange 2010 includes the following server roles:
Server mailboxes on this server hosts the mailboxes and public folders. Client Access server in the server hosted client protocol, such as POP3, IMAP4, HTTPS, mobile Outlook, service availability and service auto-discovery. Server Unified Messaging This server connects the internal PBX and Exchange 2010. Hub Transport server is routing mail routes the internally Exchange. Edge Transport server is routing mail, which is usually placed at the boundary of the topology and routes the incoming and outgoing mail in your organization Exchange.
Standard design requires a Client Access server farm with load balancing for high availability and performance solutions. For Exchange 2010, you can use softovoy Balancing Windows Network Load Balancing (WNLB) but with the following restrictions: WNLB can not be used in conjunction with database availability groups (DAGs) – functionality allows you to sync mailboxes across multiple sites. Due to performance issues do not recommend running more than 8 Client Access servers balancing WNLB. WNLB can not detect a denial of service on servers and only works at the level of L3, ie, determines the availability of servers based on IP. That is, if the server responds to IP, but server applications do not work, you want to remove the failed server client access from the pool balance manually. WNLB configuration errors can lead to degradation of network bandwidth. As WNLB balancing exercises only at the client, with a limited pool of client addresses, for example when using NAT, load balancing between servers, Client Access does not work effectively.
All these problems are eliminates by the use of hardware balancers Brocade ServerIron ADX, which balances the load on the levels of L4-L7, with a maximum capacity per chassis up to 70Gbps, allow you to choose from a variety of mechanisms to balance and carry out constant monitoring of servers from the IP-availability and load SNMP and ending with an extended Health check up to check the response given on the application.
The joint solution of Brocade and Microsoft have passed laboratory testing in the Microsoft Enterprise Engineering Center (EEC) in the Microsoft headquarters in Redmond.
In this scheme, ServerIron ADX provides:
* Save sessions. Client to connect to one of the servers continues to work with him only within the session.
* Rules of switching content (Content Switching Rules). Through support for switching at the level of L7, ADX can make decisions on balancing traffic based on data about the URL, cookes, or ID SSL-session
* SSL-proxy – the maintenance of a secure tunnel between client and server with the possibility of balancing at the application level
Monitoring the north to control their availability and willingness to process requests.