Windows Azure Load Balancing session remains

Windows Azure Load Balancer defaults to 5-tuple hash: Source address, source port, destination address, destination port, protocol. That is, only session packets with exactly the same five tuples will be forwarded to the same back-end server. Obviously, for the vast majority of users with NAT Internet access, the 5-tuple does not have a session-hold function. The IPv4 is getting less and IPv6 still floating.

From an application perspective, in particular, some early Web applications do not have the ability to centralize management, and the session is stored in the Web server memory. In order to migrate to Windows Azure and modify the code, users will always feel uncomfortable, although we have thousands of reasons to persuade customers how meaningful this is.

The load balancer for Windows Azure already supports both 2-tuple hash and 3-tuple hash-mode loads, and it's plain that the source and destination ports are removed from the original 5-tuple. This way, the source address, destination address, and protocol in the session packet will not change even if you are surfing the Internet through NAT. Only the 2, 3-tuple hash mode load balancer can now be created and used only through PowerShell.

For a load balancer that already exists, you can use the following PowerShell script to set it to a 2-tuple hash mode for session persistence based on four-tier load balancing:

" SourceIP " -servicename [Cloud service name]-lbsetname [load balancer set name]

If you want to set to 3-tuple hash mode, change [SourceIP] in the above script to [Sourceipprotocol].

Windows Azure Load Balancing session remains