Only One Default Gateway Allowed on Proxy Server

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When you use a Winsock proxy or web proxy client, and if the Proxy Serveris configured with more than one default gateway, you may get the followingerror message or related error messages:
Connection timed out
The Proxy Server documentation states the following:
   A Microsoft Proxy Server computer should have only one IP default   gateway. The IP address of the default gateway should be configured on   the external network adapter card only.   This requirement is a result of the basic architecture of TCP/IP. Only   one default gateway must be defined on a host that resides on 2 or more   non-connected networks.      If the Proxy server is configured with more than one network interface, it   is connected to two networks that are by design non-connected.   A default gateway is a router that is supposed to be used for all   traffic that has no specific route. If you have two default-gateways,   the proxy server TCP/IP stack will assume that they lead to the same set   of networks. This will cause the proxy server to send Internet traffic   to the internal network, or internal traffic to the Internet.				
Remove the default gateway from the advanced TCP/IP settings of theinternal network interface on the Proxy Server and define static routes tothe internal network segments.

Because no default gateway will be defined for the internal network, youmust add static routes using the Route Add command. These routes can bemade persistent by using the -p command switch.

For additional information on adding static routes to the routing table,see the following:
  • Type route /? for additional command switches.

  • See the following Microsoft Knowledge Base article:
    140859 TCP/IP Routing Basics for Windows NT
This is not specific to Proxy Server. When the Microsoft Exchange DynamicRAS connector contacts an ISP, you can get the above error message;however, the workaround is the same.
proxy internet server timeout connect fail faq frequently asked questions winsock

Article ID: 161380 - Last Review: 12/04/2015 16:00:19 - Revision: 1.0

Microsoft Proxy Server 1.0 Standard Edition, Microsoft Proxy Server 2.0 Standard Edition

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