Problems with IP masquerading

pilot1 · 07-15-2003, 03:31 PM

Yes, it is.
But that doesn't help me, because the packets aren't reaching my Linux router.
They are going wirelessly from my desktop to my wireless router, and the wireless router is giving the error - they aren't going from my wireless router to my Linux router.
Remember, for all intents and purposes, the wireless router isn't connected to the internet, since my Linux router is just plugged into a normal port.

hakcenter · 07-15-2003, 03:41 PM

well it looks like you got a nice big fat misconfiguration, cause it will work

you know that your clients arent using the linux machine for their default gateway

manually specify 1 client computer on the same subnet and use the linux ip as the gateway, which you specified as 192.168.1.102

hakcenter · 07-15-2003, 03:46 PM

Im just going to redesign this whole thing on the thread because im bored

A = machine1
B = machine2
C = machine3

X = wireless router
Z = linux router

--------------- X
| | | |
A B C Z

Heres your IP setup

X = 192.168.1.1

A = 192.168.1.5
B = 192.168.1.6
C = 192.168.1.7

Z = 192.168.1.254

default gateway = 192.168.1.254
dns server = 192.168.1.254

and hopefully your running named on your linux machine, otherwise you must use the dns servers specified on your linux WAN eth,

/etc/resolv.conf

should have entries for those.

pilot1 · 07-15-2003, 03:47 PM

I'm not sure what you're telling me to do - correct me if i'm wrong.

You want me to set a client computer to use the Linux Router's IP as the default gateway, correct?

That's what i've been doing the entire time, and for some reason the packets aren't getting past my Linksys router.

I'm not running named, but I already have /etc/resolv.conf set up correctly on my client computers.

hakcenter · 07-15-2003, 03:50 PM

all machines should be hooked up on the linksys switch side, and nothing on the wan

getting past the router is not an option because you wont be USING the router for anything but connectivity.

pilot1 · 07-15-2003, 03:52 PM

Machine Z has eth0 connected to the WAN. eth1 on the same computer is connected to a port on the router. Everything else is accessing the router wirelessly.

That is correct, right?

When I said the packets weren't getting past my Linksys router(X), I meant they weren't going from my Linksys router(X) to the Linux router(Z) plugged into a port on the Linksys router(X).

pilot1 · 07-15-2003, 03:59 PM

If you look at that ping command I pasted then you'll see that the "Network unreachable" error message was coming from Machine X - if it had gotten to my Linux router(Machine Z) it would have been coming from Machine Z.

hakcenter · 07-15-2003, 04:00 PM

absolutely not

you are no longer USING the router for anything but a switch

linux machine connection is as follows:
dhcp to modem
static to router, SWITCH port

machines a-c, SWITCH ports

disable your routers dhcp server

pilot1 · 07-15-2003, 04:02 PM

All my clients are set to use static IPs, the dhcp server running on my router shouldn't have any effect on them, but I can still disable it. I'm not sure why that would effect anything, though.

And I know i'm only using the router as a switch, I have the network configured exactly as you just said above.

hakcenter · 07-15-2003, 04:04 PM

the above mentions WAN

you should not be using that for anything now, and not using the uplink as well.

192.168.1.1 should not even show up in the route.

pilot1 · 07-15-2003, 04:06 PM

When I refer to the WAN i'm referring to my cable modem/connection from eth0 to the WAN(internet).

I am not using the uplink or WAN ports for anything. The only port in use on my "switch" is one normal port.

hakcenter · 07-15-2003, 04:15 PM

whats the route of the linux machine currently?

pilot1 · 07-15-2003, 04:21 PM

Here it is:

Code:

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.1.0      *               255.255.255.0      U     0      0        0 eth1
<MyIP>           *               255.255.0.0        U     0      0        0 eth0
127.0.0.0        *               255.0.0.0          U     0      0        0 lo
default         <MyIP'sHostname> 0.0.0.0            UG    0      0        0 eth0
default         192.168.1.1               0.0.0.0            UG    0     0         0  eth1

I just noticed that the second default gateway is set to my switches IP, that is correct, right?

hakcenter · 07-15-2003, 04:25 PM

You should only have 1 default gateway on the linux, otherwise, as you can tell, any packets coming on the eth1 is being routed to 192.168.1.1, and end there, instead of being routed to eth0 and its default gateway

route del -host default dev eth1

something like that

pilot1 · 07-15-2003, 04:26 PM

It's route del default gw dev eth1 (Or maybe it's a little different - I don't remember.)

But when I remove that I can no longer ping the Linux router from the client computers, and eth1 says it has sent and recieved 0 packets.

I was never able to ping my client computers from the Linux router and visa versa, until someone suggested adding the gateway.