network issue

[Matt_T_hat]

I have a dual PII box that I fancied reserecting as a server.

I have gotten basic debian on it and booted as far as APT to grab the rest enough to make it a test and development webserver for my own personal use.

Debian is behaving very but the link to the outside world is not working.

The Deb PC is on a local LAN via a 8 port 10/100 switch with an XP PC.

The XP PC has an additional WiFi card and connects to the Wireless Access Point.

The WAP is connected via ethernet to a 4 port switched hub and router which connects to my 2Mbit ADSL.

A small hack to the registry causes the XP box to route for the first LAN onto the second LAN.

LAN #1 - WiFi - LAN #2 - ADSL

The XP box and the Deb box (apart from using a KVM) can ping each other nicely.

The Debian Box can ping the WiFi Access Point and even the router.

It can not ping Google or my PC in the living room (LAN # 2) the packets are going but they are not coming back.

Interestingly the XP PC also runs apache 2 and php and I test my plugins on it. I can not ping the PC by name only IP address.

LAN #1 has IPs that follow the pattern 192.168.144.x (Class C private IPs) masked 255.255.255.0

LAN # 2 has IPs dished out by the router DHCP that follow 10.0.0.x (Class A private block) masked 255.0.0.0

The router is at 10.0.0.2 and the WAP at 10.0.0.1 no unit has an IP about 10.0.0.20 (custom limit).

The router has a built in firewall and allows all of Class A and Class C private blocks in both directions.

What have I missed?

UPDATE: I have successfulyl pinged 10.0.0.6 (which I assume is the IP of my wifes PC on LAN #2) from the debian PC.

[Al42]

You have many, many issues here.

"I can not ping the PC by name only IP address." What's doing your DNS? Probably nothing, which is why you can't resolve the PC's name to its IP address. (You'd have to run a local DNS server, or put the PC in your hosts file on every computer you wanted to be able to use the PC's name.)

Is the WAP also a router, or is it just a WAP? (Is it doing its own NAT? It appears to be doing NAT to a 192 subnet.)

Is the ADSL modem doing NAT?

The PII box is behind 2 routers - the real router and the PC, which has to be doing NAT, and which is confusing the PII box. If the WAP is doing the NAT to the 192 subnet, you have 3 address translations going from the world to the PII box - you probably aren't going to get incoming requests from anything on the 10 subnet to the server, and almost definitely nothing from the world to the server.

Go to http://forum.portforward.com and post in the hardware section, including model numbers for the modem and WAP, and include the fact that the server is using Internet Connection Sharing from the PC, which is connected through the WAPwhich is connected to the internet through the router. Someone may have some idea of a trick to get requests through 3 NAT devices, but I've never heard of anyone being successful trying it.

"The router has a built in firewall and allows all of Class A and Class C private blocks in both directions." Usually it's one or the other. Routers block all incoming requests by default (coming in from the WAN, not from the LAN). Since 192 and 10 aren't legal on the WAN side, the router will never see requests from those addresses.

(Add a wireless card to the PII, turn off NAT on the WAP and it'll probably work "out of the box", if the modem isn't also doing NAT [in which case just replace the router with a switch].)

[Matt_T_hat]

Thanks that's given me something to look at.

The WAP is just the link between the XP-PC/Router and the Switch+ADSL+Router.

It would seem from what you say that the XP-PC/Router while acting as the router for the 192.x.x.x may not be doing NAT...

Yes the only DNS is the Switch+ADSL+Router box so that little mystery is solved (cheers). However any bad address dissappears into the either (!) say 10.0.0.55 (which would not be allowed by the Switch+ADSL+Router).

So the issue is the XP-PC/Router.

OK getting to the bottom of this so that is good.

I'll stop typeing now and go follow that link.

[Matt_T_hat]

Dang, the sign-up fails to send the email...

[Al42]

The WAP is just the link between the XP-PC/Router and the Switch+ADSL+Router.

Two routers?

It would seem from what you say that the XP-PC/Router while acting as the router for the 192.x.x.x may not be doing NAT...

What's doing the NAT between the 10. subnet andf the 192. subnet?

So the issue is the XP-PC/Router.

The main issue is the multiple network address translations. Pick a NAT device and use it - one and only one.

Connect a computer, set to automatically get an IP address, directly to the modem. What subnet does it get? 10? 192? Some public address?

If it's not getting a public address, your modem is doing NAT. There would be two solutions - set the modem to bridging mode (your ISP would also have to make changes on their end - and it's a normal thing for them to be asked to do) or let the modem do the translation and turn off all other routing.

If the WAP is doing translation, turn that off. You want a WAP, not a wireless router. (Although I can't see why you'd use both a router and a wireless router, other than the fact that most WAPs come with NAT turned on by default, and they have no instructions for running with no routing.) If your WAP is a router, you'll have to plug the CAT 5 into one of its LAN jacks, not its WAN jack. You're emasculating the router in that box.

Bottom line - from the internet to any given computer there should only be ONE address translation, and the device doing it should have Port 80 (if you're running a http server) forwarded to the (static internal) address of the computer the server is running on. (Some routers, rightly, won't forward ports to leased addresses.)

So ...

Check each device that could translate addresses - modem, router, WAP and computer doing ICS, in sequence (from the modem in), and finish up with only one of them doing any translation. Then assign a fixed address to the server and forward port 80, in whatever is doing the address translation, to that computer. Turn off all incoming firewalls (most routers do a better job than software running on a workstation). Connect (from outside your network) to your external address and you should get to your server.

[Matt_T_hat]

If the WAP is doing translation, turn that off. You want a WAP, not a wireless router. (Although I can't see why you'd use both a router and a wireless router, other than the fact that most WAPs come with NAT turned on by default, and they have no instructions for running with no routing.) If your WAP is a router, you'll have to plug the CAT 5 into one of its LAN jacks, not its WAN jack. You're emasculating the router in that box.

The WAP is just a WAP which is what the XP box uses to get to the rest of the network (and the DSL router). The XP box is also on the second LAN with the linux box and the linux box want access to the router (via XP box onto wifi of off wifi onto LAN off LAN onto DSL).

I know the DSL router is doing NAT as it says so on the settings. I have not notice NAT on the WAP and as for finding it on the XP box... (let's just say I don't think it is).

If LAN1 and LAN2 used the same subnet say LAN1 had 10.0.0.1-199 and LAN2 had the rest would this simplfy things or be beside the point (networks are not my thing so it takes me a while to get my head arround them.)