Windows 2000 MTU settings...

We've found a problem with win2k, and the dial-in service that our ISP, "Telstra" supplies...


[quote]Issues with Service Pack 2 under Windows 2000

Please note that there is a serious issue with DialIP and Windows 2000 Service Pack 2 which affects the operation of the Lotus Notes client when accessing mail via DialIP.

The DialIP network is built upon an underlying Frame Relay network. Frame Relay uses an MTU size of 1472 for Ethernet packets. When a windows 2000 workstation attaches to any dialup service it uses an MTU discovery process to determine the MTU size that is being used an adjusts the MTU size accordingly. Under Service Pack 2 it appears that the workstation incorrectly determines the MTU size is greater than 1472 when connecting to the DialIP network. This doesn’t happen when connecting to dialup services that are not based on frame relay, such as normal ISP dialup. As a result of the incorrectly determined MTU size, packet fragmentation occurs with the main effect being that the Lotus Notes client encounters a timeout error when the user attempts to send and email. Outside of Lotus Notes, this issue also results in an intermittent failure of routing as soon as a large amount of data is transferred.
The current workaround for this problem is to rollback to Windows 2000 Service Pack 1 for any user accessing the network via DialIP. It is anticipated that this fault will be resolved in Service Pack 3 when released. <hr></blockquote>

Anyone know how to fix this? or when service pack 3 is being released?

well I don't know of a fix that will enable Win2k to correctly identify the Max MTU size. However you can set settings manually yto optimize your connection:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\Services\T cpip\Parameters

find out with your ISP what are they're optimized settings ...

this is a workaround but it will enable you to take full advantage of your connection.

after you set it up right you can export that reg file and run it wsing a script on your domain...


Hope it helps.