# destination host unreachable

## xodarap

I need help configuring my network. I use a Wireless Bridge to connect to a Linksys Wireless Router. The bridge is attached to a switch and so is the gentoo box.

Linksys Wireless Router <--> D-Link DWL G810 Wireless Bridge <--> Switch <--> Gentoo box

Heres a brief note on what the gentoo box is caple of doing:

Able:

ping the D-Link Wireless Bridge from the gentoo box successfully

ping other computers connected to the switch.

Unable:

ping the Linksys Wireless Router

ping any server on the net

Help please!

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## NeddySeagoon

xodarap,

Can you do a sketch, ASCII art is fine, showing the connections and the IP addresses assiged to each interface. Obscure your public IP if you wish.

If you assign IP addresses using DHCP, knowing that will be useful too.

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## xodarap

Thanks for replying, what follows is a key for the image below:

- black solid lines: wired connections

- blue curvy lines: wireless connections

- black broken line: Physical seperation (2 different Rooms) which explains why  its such a strange setup

- red line: surrounds the gentoo box that possess the problem

I don't think there's a DHCP server running, but the laptop is capable of receiving an IP without me assigning a static ip, so maybe I'm wrong. Nevertheless, I'd like to continue to assign static ip's even if the Linksys router acts as a DHCP server.  I'm a linux/gentoo newbie, so perhaps I've made some incorrect assumptions?

Here's the Image:

www.geocities.com/paradoxitis/netmap.gif

Thanks for your help.

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## NeddySeagoon

xodarap,

That makes things clearer. A few clarifications

1. Your wireless bridge operates in transparent bridge mode, so the IP it has is only to admin it?

2. The Windows/Redhat box (next to Gentoo problem box) correct IP is 192.168.1.200?

Can you provide the following from the Gentoo box at 192.168.1.175

The output of 

```
/sbin/route
```

The content of 

```
/etc/resolv.conf
```

The output of 

```
ifconfig eth0
```

I'm not sure I actually need that last bit, so if you have to type it up, omit it just now.

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## xodarap

Response to points 1 and 2:

1. Yeah, I use it to configure/admin the bridge, what is transparent bridge mode?

2. You're right.

Outputs

/sbin/route :

```
Kernel IP routing table

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

192.168.1.0     *               255.255.255.0   U     0      0        0 eth0

loopback        gentoobox.local 255.0.0.0       UG    0      0        0 lo

default         192.168.1.1     0.0.0.0         UG    0      0        0 eth0

```

/etc/resolv.conf :

```
domain localnet

nameserver 192.168.1.9

nameserver 216.148.227.68

# In the analogous RedHat resolv.conf file there exist the following line

#search   realmspace.com

```

ifconfig eth0 :

```
eth0      Link encap:Ethernet  HWaddr 00:10:4B:64:F8:D1

          inet addr:192.168.1.175  Bcast:192.168.1.255  Mask:255.255.255.0

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:14752 errors:0 dropped:0 overruns:0 frame:0

          TX packets:3150 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000

          RX bytes:2892604 (2.7 Mb)  TX bytes:349728 (341.5 Kb)

          Interrupt:9 Base address:0xfc00

```

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## NeddySeagoon

xodarap,

Transparent bridge mode is a way of operating a bridge so that you can have the same network address both sides. In your case, the 192.168.1. network.

Your /etc/resolv.conf looks a bit strange.

I'm not sure what the  *Quote:*   

>  domain localnet 

 entry does. The man page doesn't help much either.

Do you really have a nameserver at 192.168.1.9 ?

If not name resolution will get very slow because the PC will always wait for the timeout. 

Your Linksys Router probably does name serving so 192.168.1.1 may be better.

I guess that 216.148.227.68 is your ISP nameserver?

I can ping it so its alive and well.

Before you change anything, try the following.

Ping 216.239.57.99 from the Gentoo box. That will check your route

Try browsing http://216.239.57.99 too. If all that works, its a name resolution problem for sure..

Now a daft question. A lot of wireless networking equipment will only allow connections from known MAC addresses. 

If you have turned this on, have you registered 00:10:4B:64:F8:D1 so your Gentoo box is known?

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## xodarap

Neddy,

216.148.227.68 is my ISP's nameserver

I tried pinging 216.239.57.99 but I was unable to do so from the gentoo box, I couldn't browse it from the gentoo box either.

 *Quote:*   

> Now a daft question. A lot of wireless networking equipment will only allow connections from known MAC addresses.
> 
> If you have turned this on, have you registered 00:10:4B:64:F8:D1 so your Gentoo box is known?

 

Yeah I've checked, that wasn't the case. MAC address filtering isn't being implemented.

Any other suggestions? Its really odd, I have no idea why it doesn't work.

Even after I changed the nameserver to 192.168.1.1 it didn't work.

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## xodarap

It still says Destination Host unreachable

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## NeddySeagoon

xodarap,

Can you connect the Gentoo box to the Linksys router with a wire?

Just for testing.

You could carry the base unit through and ssh into it to save moving a monitor. You may even be able to ssh in from 192.158.1.200.

Do the ping and browser tests I described earlier.

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## xodarap

Neddy,

I connected the gentoo box directly to the Linksys router.

I was able to ssh into the gentoo box from 192.168.1.200

I can ping google from the gentoo box. I then emerged lynx to see if I could browse google, which is also possible. 

so what do I do? What exactly is a name resolution problem and what do I do to fix it, if that is what the problem is.

On another note I noticed when the gentoo box starts it says some local file system failed to mount after some usb messages. I doubt this has anything to do with the problem at hand though.

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## krinn

Check the DWL810 manual page 18-23

Things important to note:

- DWL-810 and the Linksys router MUST have same SSID

- Same for Channel

- You must use it in Infrastructure mode

- Make sure the DWL & router have the same encryption algo and key

- computers: 192.168.1.175, 192.168.1.200 should have gateway set to 192.168.1.30 (and not 192.168.1.1, let's trust doc first -> the DWL should forward them to your router as seen in HOME tab section -> Gateway info from the DWL)

- If all fail, try disable security on router and DWL until it work then reenable it (sometimes can be a pain just because you mistake a number of the secure key)

ftp://ftp.dlink.com/Wireless/dwl810+/Manual/dwl810+_manual_103.zip

it's version 810+, unsure they change many things, but should be close enought to act similar to yours

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## xodarap

I had a look at the documentation for the G810, Krinn I don't think you're right because the G810 cannot act as a gateway. But thanks for the suggestion. 

I emailed D-Link support and they replied, stating that the device uses the MAC address of the computer that configures it, to identify a client. Hence, it is not possible to share the connection in the manner I attempted to facilitate. I'm thinking of using 2 NICS on the windows box and using Internet Connection Sharing (ICS) as a temporary measure. But perhaps I could clone the MAC address of the switch and configure the G810 using that MAC address. That might be a solution, although the marginal gains might not be worth the effort. This assuming ofcourse that I can identify the MAC address of the switch, if they do in fact have MAC addresses. Do you know how I might go about doing this? Do switches have MAC addresses and how do I find out what it/they are?

Thanks for all you're help Neddy, I was able to connect the gentoo box to the internet after configuring the G810 from it. I really appreciate you're help. Heard the University of Edinburgh has an excellent Robotics programme, comment?

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## NeddySeagoon

xodarap,

So you do have MAC filtering, the filter table contains eactly one MAC address. Thats a bit brain dead. I suspect its a marketing ploy, so they have can have two identical devices at the hardware level and load different firmware to charge vastly different prices. Not that I'm suggesting you should  look around for a firmware hack or try other than the intended firmware.

This page has a firmware update  dated 16 Aug 2004 so it may be worth trying. http://support.dlink.com/products/view.asp?productid=DWL%2D810%2B

If you are up for a bit of light hacking, you could try to use the gentoo box with the MAC adddress set to all  zeros and/or all FFs to configure the bridge. Those  addresses are illegal and one of them may well match anything. (I'll need to read up on ifconfig to work out how)

Not all Linux NIC drivers support MAC spoofing however. 

The switch does not have a MAC address of its own, so making it look like the switch set up the bridge is a non starter. It learns (by trial and error) which MAC addresses are on which port and remembers, so that traffic is only 'switched' to the required port.

You may not have two boxes with the same MAC address on the same network either. Thats how packets find their way around. In fact MAC addresses are supposed to be unique.

I've looked at reorganising the bits you have too but using the bridge off your modem and putting the wireless router in the other room doesn't help.

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## krinn

 *xodarap wrote:*   

> Krinn I don't think you're right because the G810 cannot act as a gateway. But thanks for the suggestion. 
> 
> 

 

1/ Wrong, if you look at windows installation you will see they setup the network card under windows and ask user to setup the G810 IP as gateway.

So i'm certain (if manual is correct) that the G810 can be use as gateway.

2/ If you look (can't post it) at the picture from quickinstall (one that show setup of the DWL810) you will see that a GATEWAY entry (cannot edit it, but show as info) exist

The idea a GATEWAY entry exist just let me guess that (yes GUESS this time)

1/ your DWL810 connect to the router by identify it with same SSID and channel and key as itself

2/ DWL810 then saved the IP of the router as its gateway

3/ your card are connect to DWL810 and use its IP as gateway

4/ DWL810 forward info thru its gateway (so the router IP)

It's just guessing, but you should try to see what info you can grab from that GATEWAY inside the DWL810 configuration.

ps: you can spoof MAC address with ethereal

-> set the G810 as gateway with a card, access its menu http://192168.0.30 and see MAC address in ethereal

ps2: ANY material that need a setup in a network MUST have a MAC address, that means not all switch have a MAC address but in your case, it must have one.

It's simple, if you need to access a material you can't relly on IP but on its MAC address, that's why masquerading exist and work.

When sending info to an IP, inside packet are coded the MAC address of material that you wish info to be delivered. This is how your computers can received info while they all use the same internet IP address.

ps3: forget about ethereal because the DW810 gives you also its MAC address in the HOME part in its configuration.

In all case, the most important part for me is to be sure the gateway info on your DWL is set as your router IP address, if not, the DWL can't connect to the router for a reason (bad SSID, key, channel or connection (big wall, distance...))

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## NeddySeagoon

krinn,

I think its safe to say that the RedHat/Windows box on 192.169.1.200 can connect everywhere, so all the wireless setup is OK.channel SSID WEP keys and so on.

Its not just a name resolution issue, because pinging google.com by IP address fails. therfore there is a routing problem too. (There may not even be a name resolution issue)

I don't see the bit in the manual that asks for the 810 to be set as a gateway. It askes for the gateway address to be entered in the setup and includes some additional explaination in brackets. 

If you are refering to Page 20, which sets up a Windows box with a static IP, in prepartaion to configure the 810, then the request to enter the LAN IP address of the wireless router is not really required. The router on the network may not be wireless anyway.

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## krinn

not speaking about dns yet, yeah

i have forgot the fact the 192.168.0.200 is working, so network should be ok...

Can you do a traceroute from 192.168.0.200 to 192.168.1.1 to see path taken ?

Maybe something will show up...

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## xodarap

season's greetings!

Neddy I had already downloaded the firmware update dated 16 Aug 2004, but that didn't change much. I've been trying to find a firmware hack but to no avail, but I came across some interesting hacks for Linksys routers. 

Krinn, thanks for the hint on ethereal, it's something I've been wanting to learn how to use. 

I've found a solution that works, although it has some flaws and it's not the safest way to do things. It was nevertheless a quick fix. I added an extra NIC I had to the Windows box and configured it with Internet connection sharing.  So the DWL connects straight to the windows box and the windows box is connected to the switch. The switch in turn is connected to the gentoo box. It doesn't allow me to use the gentoo box as a server because it can't be accessed from an external network, but, it allows me to download software and use portage. So, it enables me to configure me gentoo box before releasing it onto the net. But what I will eventually do is switch the position of the gentoo and the windows box's and use it as a DNS server as well. 

Thanks for all your help fellow gen2ans, it's much appreciated. Neddy, got your pm. Christmas hols are nearing its end, back to school it shall be.  cheers to you both, merry christmas and a happy new year.

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