Accessing 2 networks from 1 PC

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Guest

I have 2 NIC's in one PC. One NIC has static IP settings which allow the
computer to access a network in another location through a point to point
line. For Information, this is a 172. network with a 172. gateway and DNS.
The second network card I would like to use to access the internet through
the local router on my "internal" network with 192. type settings. As you
might expect, if I disable the 192. card, I can get to the 172. network.
When I re-enable the 192. card, I cannot get onto the internet and traffic to
the 172. side slows down alot. I have tried playing with binding orders and
changing metrics. No real results. I am pretty sure I could solve problems
with establishing persistent routes, but I am not sure how to do it. These
machines are XP SP2. Any ideas would be helpful. I have about 10 computers
I need to solve this problem on.
 
I have 2 NIC's in one PC. One NIC has static IP settings which allow the
computer to access a network in another location through a point to point
line. For Information, this is a 172. network with a 172. gateway and DNS.
The second network card I would like to use to access the internet through
the local router on my "internal" network with 192. type settings. As you
might expect, if I disable the 192. card, I can get to the 172. network.
When I re-enable the 192. card, I cannot get onto the internet and traffic to
the 172. side slows down alot. I have tried playing with binding orders and
changing metrics. No real results. I am pretty sure I could solve problems
with establishing persistent routes, but I am not sure how to do it. These
machines are XP SP2. Any ideas would be helpful. I have about 10 computers
I need to solve this problem on.
Click to expand...

Please post a news group reply that includes a copy of the TCP/IP
route table from one of the computers. You can write the route table
to a file with this command:

route print >route.txt

I assume that the IP addresses are in the ranges
172.16.0.0-172.31.255.255 and 192.168.0.0-192.168.255.255. Those are
private, non-routeable addresses, so there's no risk to posting your
full routing information.

Do the computers ever use the 172. network for Internet access?
 
--
Larry


Steve Winograd said:
Please post a news group reply that includes a copy of the TCP/IP
route table from one of the computers. You can write the route table
to a file with this command:

route print >route.txt

I assume that the IP addresses are in the ranges
172.16.0.0-172.31.255.255 and 192.168.0.0-192.168.255.255. Those are
private, non-routeable addresses, so there's no risk to posting your
full routing information.

Do the computers ever use the 172. network for Internet access?
Click to expand...


Steve, thanks for your reply. I will get a copy of the routing table today.
To answer one of your questions, no the 172. network does not access the
internet. Problem is, when I tried to remove the default gateway ( 172...),
I got no access to the network on the 172 side.

Larry
 
Steve,

Here is the route print from one of the affected systems.

===========================================================================
Interface List
0x1 ........................... MS TCP Loopback interface
0x2 ...00 09 6b 43 cd d4 ...... Intel(R) PRO/100 VE Network Connection -
Packet Scheduler Miniport
0x10004 ...00 30 bd e0 2a 9e ...... Belkin 11Mbps Wireless Desktop PCI
Adapter (F5D6001 V.2) - Packet Scheduler Miniport
===========================================================================
===========================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 172.24.4.254 172.24.4.110 30
0.0.0.0 0.0.0.0 192.168.111.1 192.168.111.8 30
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
172.24.4.0 255.255.255.0 172.24.4.110 172.24.4.110 30
172.24.4.110 255.255.255.255 127.0.0.1 127.0.0.1 30
172.24.255.255 255.255.255.255 172.24.4.110 172.24.4.110 30
192.168.111.0 255.255.255.0 192.168.111.8 192.168.111.8 30
192.168.111.8 255.255.255.255 127.0.0.1 127.0.0.1 30
192.168.111.255 255.255.255.255 192.168.111.8 192.168.111.8 30
224.0.0.0 240.0.0.0 172.24.4.110 172.24.4.110 30
224.0.0.0 240.0.0.0 192.168.111.8 192.168.111.8 30
255.255.255.255 255.255.255.255 172.24.4.110 172.24.4.110 1
255.255.255.255 255.255.255.255 192.168.111.8 192.168.111.8 1
Default Gateway: 192.168.111.1
===========================================================================
Persistent Routes:
None
 
Steve,

Here is the route print from one of the affected systems.

===========================================================================
Interface List
0x1 ........................... MS TCP Loopback interface
0x2 ...00 09 6b 43 cd d4 ...... Intel(R) PRO/100 VE Network Connection -
Packet Scheduler Miniport
0x10004 ...00 30 bd e0 2a 9e ...... Belkin 11Mbps Wireless Desktop PCI
Adapter (F5D6001 V.2) - Packet Scheduler Miniport
===========================================================================
===========================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 172.24.4.254 172.24.4.110 30
0.0.0.0 0.0.0.0 192.168.111.1 192.168.111.8 30
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
172.24.4.0 255.255.255.0 172.24.4.110 172.24.4.110 30
172.24.4.110 255.255.255.255 127.0.0.1 127.0.0.1 30
172.24.255.255 255.255.255.255 172.24.4.110 172.24.4.110 30
192.168.111.0 255.255.255.0 192.168.111.8 192.168.111.8 30
192.168.111.8 255.255.255.255 127.0.0.1 127.0.0.1 30
192.168.111.255 255.255.255.255 192.168.111.8 192.168.111.8 30
224.0.0.0 240.0.0.0 172.24.4.110 172.24.4.110 30
224.0.0.0 240.0.0.0 192.168.111.8 192.168.111.8 30
255.255.255.255 255.255.255.255 172.24.4.110 172.24.4.110 1
255.255.255.255 255.255.255.255 192.168.111.8 192.168.111.8 1
Default Gateway: 192.168.111.1
===========================================================================
Persistent Routes:
None
Click to expand...

Thanks for providing the route table, Larry. The problem that I see
is that both NICs have a default route (starting with 0.0.0.0).
Windows XP uses the default route to access all IP addresses that
aren't on a local subnet. When there are two or more default routes,
Windows XP will only use one of them.

Since access to servers on the Internet uses the default route, the
one for the 172.24.4.x network has to be removed. If it's assigned
manually, simply remove it from the network connection's TCP/IP
properties. If it's assigned by a DHCP server, you can remove it in
either of these ways:

1. Configure the DHCP server not to assign it.

or:

2. Run these commands on each computer after startup to remove both
default routes and then add one that uses the 192. NIC:

route delete 0.0.0.0 mask 0.0.0.0
route add 0.0.0.0 mask 0.0.0.0 192.168.111.1
 
Thank you Steve for the very informative reply. I wanted to reply to you to
be sure I understand what your conclusion and approach is. So, let me
clarify and hopefully not sound ignorant.

The 0.0.0.0 default route on the 172 side comes from somewhere that I don't
know about. I have given that NIC a static ip, static default gateway, and
dns servers. So, I didn't intentionally put the 0.0.0.0 in anywhere unless it
is programmed in on some setting as a default. Just to clarify, I need to
connect to a computer on a different subnet through the nic that is
programmed to the 172 settings(in case it matters, the computer on the other
end is a 10.1.... computer. I get to this computer by virtue of settings in
the application I run after the 172 nic is connected to the other end). I
do not get to the internet on that nic. I do need to get to the internet on
the 192 nic which is a dhcp setting on the network this computer physically
resides on. I may be redundant here, but given what I just pointed out, does
your recommendation hold? Are default routes 0.0.0.0 just used for internet
traffic? Just trying to understand the meat of it. Thanks again.
 
Thank you Steve for the very informative reply. I wanted to reply to you to
be sure I understand what your conclusion and approach is. So, let me
clarify and hopefully not sound ignorant.

The 0.0.0.0 default route on the 172 side comes from somewhere that I don't
know about. I have given that NIC a static ip, static default gateway, and
dns servers. So, I didn't intentionally put the 0.0.0.0 in anywhere unless it
is programmed in on some setting as a default. Just to clarify, I need to
connect to a computer on a different subnet through the nic that is
programmed to the 172 settings(in case it matters, the computer on the other
end is a 10.1.... computer. I get to this computer by virtue of settings in
the application I run after the 172 nic is connected to the other end). I
do not get to the internet on that nic. I do need to get to the internet on
the 192 nic which is a dhcp setting on the network this computer physically
resides on. I may be redundant here, but given what I just pointed out, does
your recommendation hold? Are default routes 0.0.0.0 just used for internet
traffic? Just trying to understand the meat of it. Thanks again.
Click to expand...

The 0.0.0.0. default route appears because you've assigned a static
default gateway on the 172 side. Remove the default gateway address
from that NIC. You won't need to use the "route delete" or "route
add" commands that I gave.

Then, create a persistent route to enable the 172 computers to access
the 10.1 computer on the other end. This should only need to be done
once on each 172. computer:

route -p add 10.1.0.0 mask 255.255.0.0.0 172.24.4.254
 
Steve,

Thanks and you're a good guy. I will give it a try on Tuesday because I
will be out of town Monday. On the 172 side, it wouldn't work unless I gave
it the default gateway of 172.24.4.254. What I am getting from what you say
is to remove the 172 default gateway and replace it with a persistent route
using the route -p command example you gave me. Since the static default
gateway adds a 0.0.0.0 default route to the process, if you have 2 different
static gateways on the 2 nics, each of which establish the same defaukt
route, the traffic doesn't know what to do? That may explain why at times
and on some of the computers, it seems to work occasionally with the way I
have it set up. I will let you know what happens Tuesday or Wednesday and
reply. Thanks again for your knowledgable help.
 
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