Routing Issue w/ LAN and PPP 10.* networks - Please help asap

Unanswered Question
Feb 2nd, 2010

Hoping someone can help me point my network support in the right direction.  We have a Cisco router that users are making a PPP connection to (not getting a default gateway from us) via windows.  Here is a shot of the route tables before and after.  After connecting they are getting a 10.0.0.0 route added with the ip we are assigning as the gateway.  User seems to think we are passing that route to them from dhcp and network is thinking windows is creating it.

Here is the routing table before connecting…

IPv4 Route Table

===========================================================================

Interface List

0x1 ........................... MS TCP Loopback interface

0x10003 ...00 0e 0c a1 74 d4 ...... Intel(R) PRO/1000 MF Server Adapter

===========================================================================

===========================================================================

Active Routes:

Network Destination        Netmask          Gateway       Interface  Metric

          0.0.0.0          0.0.0.0         10.0.8.1        10.0.10.7     10

         10.0.8.0    255.255.252.0        10.0.10.7        10.0.10.7     10

        10.0.10.7  255.255.255.255        127.0.0.1        127.0.0.1     10

   10.255.255.255  255.255.255.255        10.0.10.7        10.0.10.7     10

        127.0.0.0        255.0.0.0        127.0.0.1        127.0.0.1      1

        224.0.0.0        240.0.0.0        10.0.10.7        10.0.10.7     10

  255.255.255.255  255.255.255.255        10.0.10.7        10.0.10.7      1

Default Gateway:          10.0.8.1

===========================================================================

Persistent Routes:

  None

Here is the routing table after connecting …

IPv4 Route Table

===========================================================================

Interface List

0x1 ........................... MS TCP Loopback interface

0x10003 ...00 0e 0c a1 74 d4 ...... Intel(R) PRO/1000 MF Server Adapter

0x6e0004 ...00 53 45 00 00 00 ...... WAN (PPP/SLIP) Interface

===========================================================================

===========================================================================

Active Routes:

Network Destination        Netmask          Gateway       Interface  Metric

          0.0.0.0          0.0.0.0         10.0.8.1        10.0.10.7     10

         10.0.0.0        255.0.0.0      10.185.0.31      10.185.0.31      1

         10.0.8.0    255.255.252.0        10.0.10.7        10.0.10.7     10

        10.0.10.7  255.255.255.255        127.0.0.1        127.0.0.1     10

      10.185.0.31  255.255.255.255        127.0.0.1        127.0.0.1     50

   10.255.255.255  255.255.255.255        10.0.10.7        10.0.10.7     10

   10.255.255.255  255.255.255.255      10.185.0.31      10.185.0.31     50

        127.0.0.0        255.0.0.0        127.0.0.1        127.0.0.1      1

        224.0.0.0        240.0.0.0        10.0.10.7        10.0.10.7     10

        224.0.0.0        240.0.0.0      10.185.0.31      10.185.0.31     50

  255.255.255.255  255.255.255.255        10.0.10.7        10.0.10.7      1

  255.255.255.255  255.255.255.255      10.185.0.31      10.185.0.31      1

Default Gateway:          10.0.8.1

===========================================================================

Persistent Routes:

  None

The highlighted route is the one that is causing us trouble.  If we take the for instance of a system with the IP of 10.0.6.6, it can only use the 0.0.0.0 or 10.0.0.0 route.  Because the netmask is longer on the 10.0.0.0 route, Windows thinks that it is the better option and sends the packets to the 10.185.0.31 gateway instead of the 10.0.8.1 gateway that it should have gone to. 

How can we remove this without making the user add persistent routes, etc.

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Giuseppe Larosa Tue, 02/02/2010 - 21:58

Hello Shaun,

may  you post the Cisco router configuration?

remove all sensitive information like username/pwds and mask public IP addresses

you may want to consider to post this under the Remote Access forum that should be the right place for this kind of issues.

Hope to help

Giuseppe

Actions

This Discussion