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Windows "routing" server separating two subnets - one subnet can reach the Internet and the other can't....computers also can't ping each other between subnets

Gurus,

I have a small lab with a bunch of servers setup on two different subnets, 
192.168.1.1 is the gateway for one and 172.16.1.1 is the gateway for the 
other.  Installed on my Router (Windows Server with three NICs - I know, 
please don't comment on this, it's is for learning purposes, not 
production), the third NIC is the gateway to the Internet.

What works:  The Router server can reach the Internet as well as the 
computers in the 192.168.1.0/24 subnet (the first subnet built).

What's broken:  The computers on the 172.16.1.0/16 subnet cannot get to the 
Internet AND no computer in either subnet can ping any computer in the other 
subnet.  What am I doing wrong?  I think I need a static route on the Router 
server but am unsure of how to configure that static route, I believe it 
needs to be configured against the 172.16.x.y NIC.  In doing that, for that 
static route, what would be my:

Destination?
Network mask?
Gateway?

Additional details:

192.168.1.0/24 subnet computer XP1:

        Host Name . . . . . . . . . . . . : XP1
        Primary Dns Suffix  . . . . . . . : alpha.local
        Node Type . . . . . . . . . . . . : Unknown
        IP Routing Enabled. . . . . . . . : No
        WINS Proxy Enabled. . . . . . . . : No
        DNS Suffix Search List. . . . . . : alpha.local
                                            alpha.local

Ethernet adapter Local Area Connection:

        Connection-specific DNS Suffix  . : alpha.local
        Description . . . . . . . . . . . : VMware Accelerated AMD PCNet
Adapter #2
        Physical Address. . . . . . . . . : 00-0C-29-4C-D8-52
        Dhcp Enabled. . . . . . . . . . . : Yes
        Autoconfiguration Enabled . . . . : Yes
        IP Address. . . . . . . . . . . . : 192.168.1.200
        Subnet Mask . . . . . . . . . . . : 255.255.255.0
        Default Gateway . . . . . . . . . : 192.168.1.1
        DHCP Server . . . . . . . . . . . : 192.168.1.10
        DNS Servers . . . . . . . . . . . : 192.168.1.10
        Lease Obtained. . . . . . . . . . : Thursday, September 18, 2008
9:31:05 PM
        Lease Expires . . . . . . . . . . : Friday, September 26, 2008
9:31:05 PM

------------------------------------------------------

172.16.1.0/16 subnet computer XP2:

        Host Name . . . . . . . . . . . . : XP2
        Primary Dns Suffix  . . . . . . . : alpha.local
        Node Type . . . . . . . . . . . . : Unknown
        IP Routing Enabled. . . . . . . . : No
        WINS Proxy Enabled. . . . . . . . : No
        DNS Suffix Search List. . . . . . : alpha.local

Ethernet adapter Local Area Connection:

        Connection-specific DNS Suffix  . :
        Description . . . . . . . . . . . : VMware Accelerated AMD PCNet
Adapter

        Physical Address. . . . . . . . . : 00-0C-29-E1-E7-07
        Dhcp Enabled. . . . . . . . . . . : No
        IP Address. . . . . . . . . . . . : 172.16.1.2
        Subnet Mask . . . . . . . . . . . : 255.255.0.0
        Default Gateway . . . . . . . . . : 171.16.1.1
        DNS Servers . . . . . . . . . . . : 192.168.1.10

--
Spin 


0
Spin
9/19/2008 7:39:56 PM
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On Sep 19, 12:39=A0pm, "Spin" <S...@invalid.com> wrote:

> I have a small lab with a bunch of servers setup on two different subnets=
,
> 192.168.1.1 is the gateway for one and 172.16.1.1 is the gateway for the
> other. =A0Installed on my Router (Windows Server with three NICs - I know=
,
> please don't comment on this, it's is for learning purposes, not
> production), the third NIC is the gateway to the Internet.
>
> What works: =A0The Router server can reach the Internet as well as the
> computers in the 192.168.1.0/24 subnet (the first subnet built).
>
> What's broken: =A0The computers on the 172.16.1.0/16 subnet cannot get to=
 the
> Internet AND no computer in either subnet can ping any computer in the ot=
her
> subnet. =A0What am I doing wrong? =A0I think I need a static route on the=
 Router
> server but am unsure of how to configure that static route, I believe it
> needs to be configured against the 172.16.x.y NIC. =A0In doing that, for =
that
> static route, what would be my:

How would a computer on the 172.16.1.0/16 subnet know to use this
machine to reach machines on the other subnet?

DS
0
David
9/19/2008 8:11:44 PM
All computers on the 172.16.1.0/16 subnet have a default gateway of 
172.16.1.1 - that is one of the interface addresses of the Windows router. 
All computers on the 172.16.1.0/16 subnet can successfully ping the gateway 
address of 172.16.1.1 but not beyond it - indicating to me a problem wiht 
how I configured my static route on the gateway machine.

So my question would be, how excatly to configure a static route(s) on the 
gateway machine such that it will forward packets between subnets? 


0
Spin
9/19/2008 9:06:34 PM
On Sep 19, 2:06=A0pm, "Spin" <S...@invalid.com> wrote:
> All computers on the 172.16.1.0/16 subnet have a default gateway of
> 172.16.1.1 - that is one of the interface addresses of the Windows router=
..
> All computers on the 172.16.1.0/16 subnet can successfully ping the gatew=
ay
> address of 172.16.1.1 but not beyond it - indicating to me a problem wiht
> how I configured my static route on the gateway machine.
>
> So my question would be, how excatly to configure a static route(s) on th=
e
> gateway machine such that it will forward packets between subnets?

No need. The interface routes should do it.

How about the return ping packets? How are machines in the 192.168.1.x
LAN supposed to know to use the gateway to reach 172.16.x.x LAN?

DS
0
David
9/19/2008 10:10:58 PM
"David Schwartz" <davids@webmaster.com> wrote in message 
news:1661705c-5380-4fc2-8dad-7df9d3c123fe@g17g2000prg.googlegroups.com...
> No need. The interface routes should do it.
>
> How about the return ping packets? How are machines in the 192.168.1.x
> LAN supposed to know to use the gateway to reach 172.16.x.x LAN?

Well, now that's my question. 


0
Spin
9/19/2008 10:41:08 PM
On Sep 19, 3:41=A0pm, "Spin" <S...@invalid.com> wrote:
> "David Schwartz" <dav...@webmaster.com> wrote in message
> news:1661705c-5380-4fc2-8dad-7df9d3c123fe@g17g2000prg.googlegroups.com...
>
> > No need. The interface routes should do it.
>
> > How about the return ping packets? How are machines in the 192.168.1.x
> > LAN supposed to know to use the gateway to reach 172.16.x.x LAN?
>
> Well, now that's my question.

There are three ways:

1) You can manually configure every machine on the 192.168.1.x LAN
with a route to 172.16.x.x.

2) You can configure the gateway on the 192.168.1.x LAN with a route
to 172.16.x.x.

3) You can use some kind of routing protocol on the 192.168.1.x LAN.

DS
0
David
9/19/2008 11:00:01 PM
Spin wrote:

> Gurus,
> 
> I have a small lab with a bunch of servers setup on two different
> subnets, 192.168.1.1 is the gateway for one and 172.16.1.1 is the
> gateway for the other.  Installed on my Router (Windows Server with
> three NICs - I know, please don't comment on this, it's is for
> learning purposes, not production), the third NIC is the gateway to
> the Internet.
> 
> What works:  The Router server can reach the Internet as well as the
> computers in the 192.168.1.0/24 subnet (the first subnet built).
> 
> What's broken:  The computers on the 172.16.1.0/16 subnet cannot get
> to the Internet AND no computer in either subnet can ping any
> computer in the other subnet.  What am I doing wrong?  I think I need
> a static route on the Router server but am unsure of how to configure
> that static route, I believe it needs to be configured against the
> 172.16.x.y NIC.  In doing that, for that static route, what would be
> my:


I'm assuming that 192.168.1.1 and 172.16.1.1/16 are your two server NIC
addresses.  And that all 192.168.1.0/24 hosts had 192.168.1.1 as the
GW.  And that 172.16.1.1 is the GW of all your 172.16.0.0 /16 hosts.

If that's the case, and you have routing enabled on your Windows
server, and you have NAT properly configured on your router/cable
modem, there's nothing wrong.

Make sure you don't have Windows FW enabled blocking the pings. And
make sure windows routing is on.


-- 

hsb


"Somehow I imagined this experience would be more rewarding" Calvin
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0
Hansang
9/19/2008 11:05:54 PM
I like option 2.  "2) You can configure the gateway on the 192.168.1.x LAN 
with a route to 172.16.x.x."  What would be my syntax for that in the form 
of a route add statement? 


0
Spin
9/20/2008 12:04:55 AM
On Sep 19, 5:04=A0pm, "Spin" <S...@invalid.com> wrote:
> I like option 2. =A0"2) You can configure the gateway on the 192.168.1.x =
LAN
> with a route to 172.16.x.x." =A0What would be my syntax for that in the f=
orm
> of a route add statement?

I'm not sure what kind of router you have, but the idea would be to
add a route to 172.16.0.0/16 (netmask 255.255.0.0) with a gateway of
192.168.1.200.

In Cisco parlance:
ip route 172.16.0.0 255.255.0.0 192.168.1.200

In Linux parlance:
route add -net 172.16.0.0 netmask 255.255.0.0 gw 192.168.1.200

DS

0
David
9/22/2008 12:14:18 AM
Was there a reason why you picked 192.168.1.200 instead of 192.168.1.1? 


0
Spin
9/22/2008 6:38:15 PM
On Sep 22, 11:38=A0am, "Spin" <S...@invalid.com> wrote:
> Was there a reason why you picked 192.168.1.200 instead of 192.168.1.1?

I thought the gateway between the two LANs *was* 192.168.1.200. If
it's not, please explain your numbering scheme including what is the
inter-LAN gateway and what is the default gateway on both LANs.

DS
0
David
9/22/2008 7:13:37 PM
Reply: