Confusion in Configuring Networks

Fred Krogh · Posted: Sat Dec 06, 2014 4:01 pm Post subject: Confusion in Configuring Networks

My primary computer has:
eth0 is for the outside world.
eth1 is a local wired network at 192.168.0.3
eth2 is connected to a wireless router at 192.168.2.3

A laptop connected to the wireless network can view the router at 191.168.1.1, and can access other stuff on 191.168.1.*

My primary computer can not see anything on the wireless network. I'm guessing that I don't have things set up correctly in /etc/conf.d/net, but I'm not clear on what must be said there to access stuff on the wireless network. Any suggestions there are elsewhere most welcome. Thanks,
Fred

NeddySeagoon · Posted: Sat Dec 06, 2014 4:09 pm Post subject:

Fred Krogh,

We need more info.

Please post

Fred Krogh · Posted: Sat Dec 06, 2014 4:18 pm Post subject:

NeddySeagoon · Posted: Sat Dec 06, 2014 4:30 pm Post subject:

Fred Krogh,

From your orinial post.

UberLord · Posted: Sat Dec 06, 2014 4:36 pm Post subject:

Any reason why the wireless is on a different subnet?

I run wired and wireless on the same subnet. I even give each wired and wireless interface the same IP address and dhcpcd works its magic and moves it to the most desired interface.
The benefit is that I can remotely connect to it regardless of how it's connected.

Anyway, in direct answer to your question you need to have a router between the wired and wireless which knows about both networks.
If you don't have this then just run them both on the same subnet.
_________________
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Fred Krogh · Posted: Sat Dec 06, 2014 4:44 pm Post subject:

I had just recently set

UberLord · Posted: Sat Dec 06, 2014 5:30 pm Post subject:

Fred Krogh · Posted: Sat Dec 06, 2014 5:43 pm Post subject:

I'm sorry, but I think I've been misleading you through confusing switch and router. My main machine is serving as a router. It is connected to the outside world (eth0) and connects to a switch (eth1) that connect to a bunch of different machine. It also connects to the wireless box (eth2).

Anyway from what you suggested, I think there is a chance that I can get this all to work. To minmize things that need to change, I'll change eth2 to 192.168.1.1/24. The router now things it is at 192.168.2.3, and I'll change that to 192.168.1.1. If I understand what was suggested that should be the only changes I need. I'll post later on how this all works out. Thanks.

Fred Krogh · Posted: Sat Dec 06, 2014 7:03 pm Post subject:

I'm not getting there. In changing things I have no wireless at all. I've done a hard reset of the wireless modem, which allegedly sets its ip address to 192.168.1.1. The documentation says that my pc and the router must be on the same subnet. So I'm guessing that this is the problem. Among other things, in /etc/cond.d/net, I have

UberLord · Posted: Sat Dec 06, 2014 7:39 pm Post subject:

You need to enable ip forwarding on the router as well - look in /etc/sysctl.conf and set

UberLord · Posted: Sat Dec 06, 2014 7:44 pm Post subject:

szatox · Advocate Joined: 27 Aug 2013 Posts: 3135

Some things there are unclear, but hey, that's what glass orb is good for :lol:

And my glass orb tells me you guys are looking for problem in a wrong place

Let's get some facts from previous posts:
pc-working-as-router has 2 subnets:
eth1 is a local wired network at 192.168.0.3
eth2 is connected to a wireless router at 192.168.2.3
wireless client is connected to 192.168.1.1.

This makes me think that the wireless device you have there is a router and not a dumb AP you expect and want to use.

Also, routers tend to have dedicated WAN interface and several wired LAN sockets. If you connected your PC to WAN port it should just work anyway. My guess is it's some ISDN router with RJ11 WAN socket so you were unable to stuff big RJ45 plug into it. You didn't want to give up this easily, so you connected it to LAN port. You also forgot to disable advanced features intended for making it "plug and play" in it's typical use case. Now the wireless box is smart enough to conflict with your PC instead of simply providing copper-to-air interface.

Have you tried running dhcp client on your eth2? I suppose it would receive a new address from 192.168.1.0 pool.

I mentioned ISDN router because it makes it sound more funny, but exacly the same mistake can be done with other routers so check ports anyway. And disable firewall and DHCP, as you most likely want to use one installed on your PC instead

Fred Krogh · Posted: Sun Dec 07, 2014 5:21 am Post subject:

Sorry, I had to leave for a bit. I've set net.ipv4.ip_forward = 1, it was set to 0 before.

That last line printed by route -n, is a mystery to me. There is nothing in /etc/* that matches 216.86.203.0, and lots that match 216.86.203.1. The change to ...forward=1, has made no discernable difference. I hope someone has the patience to help me work through this as it makes no sense to me. I am running shorewall, and looked for forward, and got the following:

NeddySeagoon · Posted: Sun Dec 07, 2014 1:23 pm Post subject:

Fred Krogh,

For help with shorewall and routing, we need /etc/shorewall/rules

szatox · Advocate Joined: 27 Aug 2013 Posts: 3135

Actually the very first post desribes this setup

Fred Krogh · Posted: Sun Dec 07, 2014 5:09 pm Post subject:

Note that I have a switch that connects to other PC's. The switch is downstairs, my main PC, and the wireless router are upstairs. It would be very awkward to change the locations of any of these.

Initially I had the wireless router connected to the internet, and that to my PC. The wireless also connected to the the switch. But I never managed to get that part of the network to work. The problem may have had to do with the way I was setting network addresses.

This is what I think (now?) should work.

NeddySeagoon · Posted: Sun Dec 07, 2014 5:42 pm Post subject:

Fred Krogh,

For this bit to work, your main PC needs to be set up as a router.

Fred Krogh · Posted: Sun Dec 07, 2014 6:25 pm Post subject:

[list=]Yes I have changed things as what I had was not working. Once the wireless router (that's an ASUS WL-520GC) was reset, that has its address at 192.168.1.1 (I think!). In /etc/shorewall.masq, I have

NeddySeagoon · Posted: Sun Dec 07, 2014 7:20 pm Post subject:

[Fred Krogh,

That all looks mostly harmless. The manual for your wireless router, it is a router, not a dumb access point, says that its default IP is 192.168.1.1

How did your PC get this setup?
code]eth2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.2 netmask 255.255.255.0 broadcast 192.168.1.255 [/code]
Your wireless router will be handing out IP addresses using dhcp now its been reset.
If this address is manually assigned, it may have been allocated by dhcp to somethinfg else too.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

Fred Krogh · Posted: Sun Dec 07, 2014 7:31 pm Post subject:

I don't usually (and don't now) have dhcpd running on my PC. When I had the wireless router working I was using it there. The stuff you referred to was set in /etc/conf.d/net which contains:

szatox · Advocate Joined: 27 Aug 2013 Posts: 3135

Well, if everything works but you just can't see wireless network from your PC (previous posts suggested you can't see your PC from wireless network), it's because SOHO routers tend to have NAT enabled by default and it filters any trafic you would like to send to wireless segment.
Also, you can't access router's configuration page from your PC because from router's perspective you are connected over WAN which makes you an attacker rather than an admin.

As a side note, you're reinventing Great Chinese Wall with your layers upon layers of NATs and routers.

Fred Krogh · Posted: Sun Dec 07, 2014 7:47 pm Post subject:

I agree with you Chinese Wall comment, but at the moment I'm just trying to get the wireless router configured. For what it is worth the wireless network is no longer showing up on my laptop so I can't even get at it from there.

Fred Krogh · Posted: Sun Dec 07, 2014 8:19 pm Post subject:

Just tried plugging the cord from my PC into a LAN port on the router. It will now respond to a ping to 192.168.1.1, but after a long time reports "This webpage is not available". There for a moment, I thought maybe I might get this sucker configured.

Fred Krogh · Posted: Mon Dec 08, 2014 5:20 pm Post subject:

I've tried linking the wireless LAN port to a laptop that runs windows xp and ubuntu. After changing the network configurations, both would ping the modem at 192.168.1.1, but neither could load that address from the browser. I have decide it is time to give up on this one. Anyone care to suggest a wireless router/switch that is Linux friendly? Thanks for all the help.
Fred

NeddySeagoon · Posted: Mon Dec 08, 2014 7:28 pm Post subject:

Fred Krogh,

Do you really need a router or would you rather use an accees point?
An access point has less to fiddle with and get right.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.