Hi All,

Today i was going through a forums some one was asking about installing windows 2003 sp2 in msexchange.org  And one of my friend Mr.Andy had given good article regarding the installation of windows 2003 sp2 so that it will help us to make better plan before we could implement.

So I taught to share this information with you all so that you can do home work before you could implement it on production environment

Windows 2003 Scalable Networking pack and its possible effects on Exchange


The above article says that when you install windows 2003 sp2 on exchange server it will loose the network connectivity, RDP connections, cluster resource also might fail or ISA blocks RDP communication.

Root cause : Microsoft released a new feature called as Scalable Networking Pack which is causing the issue and it is enabled by default and it is only used if your network card driver support them. In this scalable networking pack they have introduced new architechture - TCP Chimney Offload, Receive-side Scaling (RSS) and NetDMA.

Causes effected on the Exchange Server:
===========================
=> will loose the RDP connectivity to the server
=> slow network performance
=> RPC communication blocked by ISA
=> Can't browse IIS virtual directories
=> Cluster resources also fail.

Inorder to get rid of this issue.. once we install this sp2....

To Disable TCP Chimney, Navigate to the following registry key and set the value to 0. Note: You have to reboot the server after this registry change.

Or you can use the netsh command which I prefer without having to reboot:

If that does help with the situation, you could also try disabling the following offloading keys under the above registry hive to disable the RSS features.

One other thing to mention here is that TCP Chimney offload and NetDMA will not work with the following features enabled:

Windows Firewall
Internet Protocol security (IPsec)
Internet Protocol Network Address Translation (IPNAT)
Third-party firewalls
NDIS 5.1 intermediate drivers

The above reference helped my many technical friends to resolve the issue by disabling the tcpchimney.

Please have a look to the above url before you could plan up for installing windows 2003 sp2. i.e check your network card have the latest version patches update.