Connecting to internet through LinksysWRT54GS

[David L.]

I want to connect to the Internet through a LinksysWRT54GS router using ethernet cable. The router is plugged into an Alvarion IDU device which is connected to an antenna on the roof. The Internet connection is fixed wireless broadband.

When the PC's ethernet cable is plugged directly into the Alvarion device I am able to connect to the internet by using the Network Card Configuration dialog, saying “No� to using DHCP broadcast, entering the IP address, entering the subnet, accepting the default Broadcast address for eth0, entering the Default Gateway and entering the Nameservers. The network card is built into the ABIT NF8-V motherboard, chipset is nVidia nForce 3 250Gb single chip.

Once the PC is plugged into the Linksys router, the above configurations no longer work. I have tried saying “Yes� to the “Use DHCP broadcast?� question. I get: “Sending DHCP broadcast from device eth0� and then
“auto lo eth0�
Then the netcardconfig box disappears but neither Firefox nor Konqueror are able to find any webpages. They only get as far as “Looking up www.google.com�, for example, but they can't ever find the site. When my PC is plugged into the router, an led does light up but doesn't flicker.

A Windows XP user connected to the same Linksys router by ethernet uses the “Automatically detect settings� option in the Network Connections dialog box and that works fine for him but Knoppix doesn't seem to have such an option.

Help would be much appreciated, thanks.

[Harry Kuhman]

I want to connect to the Internet through a LinksysWRT54GS router using ethernet cable.
You certainly should be able to. I'm not sure I understand what you are connected to, but it doesn't matter. As long as the Linksys is logging into it and then taking care of the connections and giving you a NAT IP address and connection, Knoppix should connect to the Internet fine through it.


When the PC's ethernet cable is plugged directly into the Alvarion device I am able to connect....
Knoppix clealy supports your NIC. Good.


Once the PC is plugged into the Linksys router, the above configurations no longer work. I have tried saying “Yes� to the “Use DHCP broadcast?� question. I get: “Sending DHCP broadcast from device eth0� and then
“auto lo eth0�
Then the netcardconfig box disappears but neither Firefox nor Konqueror are able to find any webpages. They only get as far as “Looking up www.google.com�, for example, but they can't ever find the site. When my PC is plugged into the router, an led does light up but doesn't flicker.
This is strange. But it does sound like you have made a DHCP setup. Type a command line (shell) ifconfig at this point and tell us what you get as a response.


A Windows XP user connected to the same Linksys router by ethernet uses the “Automatically detect settings� option in the Network Connections dialog box and that works fine for him but Knoppix doesn't seem to have such an option.
In a sense Knoppix has this option, it's just the default, so you don't need to select it. My first hunch is that you have some sort of "Limit access by MAC address" feature in the Linksys that is enabled and fighting you (yes, even though the computer works from windows). If you have any such feature, disable it and try again. Also, in addition to the above ifconfig command, try to ping the Linksys router (usually at address 192.168.x.1, where x is a low digit 0 to 2) and see if you get a response to the ping (also a shell command). If that works you may have a DNS issue of some sort (although I would have expected the Linksys to resolve it). To test this try to ping 216.32.81.146 and then try to ping knoppix.net. If the first of these two pings works and the second does not then you do have a DNS setting problem, as they are pinging the same system.

Post back and we'll figure out what to do next.

[David L.]

I have done what you suggested and this is what I got:

knoppix@0[knoppix]$ ifconfig
eth0 Link encap:Ethernet HWaddr 00:50:8D:7D:67:25
inet addr:192.168.1.102 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::250:8dff:fe7d:6725/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:274 errors:0 dropped:0 overruns:0 frame:0
TX packets:53 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:19716 (19.2 KiB) TX bytes:6467 (6.3 KiB)
Interrupt:20 Base address:0xe000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:10 errors:0 dropped:0 overruns:0 frame:0
TX packets:10 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:500 (500.0 b) TX bytes:500 (500.0 b)

knoppix@0[knoppix]$ ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1): 56 data bytes
ping 192.168.1.1
ping 192.163.2.1
ping 216.32.81.146
ping knoppix.net

[Harry Kuhman]

I have done what you suggested and this is what I got.....
Well, the IF config shows that DHCP did work, you got assigned an IP address (192.168.1.102) and the related information. That the ping to 192.168.1.1 doesn't seem to work really reinforces my belief that you have some sort of MAC filtering in place and the router is not responding to your NIC because it doesn't like it's MAC address (there might be some other sort of rule in place in your router too, but in my experience MAC address filtering is the most likely choice). People often turn this on in wireless routers thinking that it makes the router more secure (it may keep neighbors from accessing you by accident, as would an encryption key, but it does not keep out hackers or make your transmissions private in any way). Since you couldn't get a ping response from the router then I'm not at all surprised or concerned that your couldn't get one from knoppix.net, and this will likely work as soon as the router ping issue is resolved. I suggest booting a Windows system and looking at all of the setup pages for the router; that's where the answer will lie.

It's worth noting that DHCP setup in routers like this will ignore any MAC filtering, which explains why you got the DHCP setup but then the router ignores you. MAC filtering only works on IP protocols, not DHCP or ARP.

By the way I don't know what firmware version you have in that Linksys or even if it's Linksys's firmware or some of the third party firmware that has been made for it, but I can tell you that others here have just connected that router and it worked (in at least one case when they couldn't even get a connection without a router).

[David L.]

Issue resolved (somewhat).

Router was switched off and on again. Computer was re-booted.
I tried to ping the router again 192.168.1.1 and got a reply.
Then I pinged another machine connected to the router and got a reply also.
Pinged 216.32.81.146 (knoppix.net) and 68.142.197.82 (yahoo.com) and got replies.
However, when I opened Firefox and typed http://68.142.197.82 I couldn't get the yahoo homepage, I just got the "transferring data" message but the page was never displayed even though I waited a few minutes.
I could not get a reply from pinging www.yahoo.com
You had suggested that it may have been a DNS issue but I couldn't find where in Knoppix to key in the DNS addresses independently of the IP, subnet, etc. As far as I could see in Knoppix, it's either yes to DHCP, which gives you no option to manually configure any of the addresses or no to DHCP and use a static IP. Since at this stage, I could see that DHCP was working to some extent I tried the Ubuntu Live CD, which allows you to use DHCP and enter DNS addresses on a separate tab. This, in fact worked (I am writing this connected through the Linksys on Ubuntu Live) but I would like to know how to supply Knoppix with the required DNS addresses.

FYI, the firmware in the Linksys is as supplied from the store. It was purchased less than two weeks ago from an online store so it should be a recent model.

[Harry Kuhman]

Issue resolved (somewhat).

Router was switched off and on again. Computer was re-booted.
I tried to ping the router again 192.168.1.1 and got a reply.
Then I pinged another machine connected to the router and got a reply also.
Pinged 216.32.81.146 (knoppix.net) and 68.142.197.82 (yahoo.com) and got replies.
However, when I opened Firefox and typed http://68.142.197.82 I couldn't get the yahoo homepage, I just got the "transferring data" message but the page was never displayed even though I waited a few minutes.....
OK, glad you're making progress. I don't think it's a DNS issue if the address I highlighted bold above doesn't work, as that is an IP address and does not need a DNS look-up to work (although some content on the page, like ads might do additional DNS lookup. Yahoo is a bad choice of a page for this test for this reason; too complex of a page). Also, I don't know how to give Knoppix just a new DNS sever, (the is likely a way I just don't know it) but you should be able to run netcardconfig again and answer no to the dhcp question and then do all of the manual settings based on the results you saw in ifconfig.

I don't know if your problem is Firefox related (unlikely but a chance) or router related (much more likely in my mind), but since the pings to Knoppix work it would be worth finding out. The best way I can think of is to try the Konquror browser (the window that opens when the CD or DVD boots) and put the www.knoppix.net URL into that address window. Also try the knoppix.net IP adress that I gave you previously. Yahoo's addresses should work too, but I have more experience with the Knoppix addresses, and see no reason to fool with Yahoo addresses that might vary by country.

And, of course, you are talking about booting Knoppix from a disc, are you not? If you've installed to hard disk all bets are off.

If we are still looking at a router issue then I would check your firmware revision and see if Linksys has a firmware update. Also, a full reset with the recessed push button rather than a simple power down and back up might help.

[David L.]

I tried keying http://216.32.81.146 into Konqueror's address bar and after a time, it did bring up the knoppix.net web page. Then I clicked "home" got back to Konqueror as file manager. I keyed www.knoppix.net into the address bar and waited. The response was:
An error occured while loading http://www.knoppix.net
Unknown host www.knoppix.net

I decided to try Firefox again, keying http://216.32.81.146 into the address bar. Down at the bottom of the window, it said "Looking up www.google-analytics.com". It produced the knoppix.net web page after about 2minutes but was still "transferring data from 216.32.81.146 after an additional minute. I suppose the point is that it found the webpage. I closed Firefox, opened it again and keyed www.knoppix.net into the address bar. After about 3 minutes the response was:
www.knoppix.net could not be found. Please check the name and try again.

I am indeed booting Knoppix from the CD, not the hard drive.
I have yet to talk to the router's owner about a firmware update.
With regard to doing a full reset with the recessed button, what will this do that power off and on again wouldn't and how is it likely to affect other users?

I was going to try using netcardconfig, saying "no" to the dhcp question and entering the information provided by ifconfig but netcardconfig asks for a Gateway address as well as an IP, Bcast and Mask. ifconfig doesn't seem to provide this. How would I get it or should I just use the default Gateway?

[Harry Kuhman]

I tried keying http://216.32.81.146 into Konqueror's address bar and after a time, it did bring up the knoppix.net web page. Then I clicked "home" got back to Konqueror as file manager. I keyed www.knoppix.net into the address bar and waited. The response was:
An error occured while loading http://www.knoppix.net
Unknown host www.knoppix.net
This is understandable, even expected. Lets use the term IP for the address that is digits and URL for the address that is a name. The IP does not need to be looked up in a name server (DNS), so you get information from Knoppix.net when you use the IP address. Unfortunately, many sites now also draw content from many places, and knoppix.net draws some ads from Google. And it accesses those ads through a URL, not an IP address. I expect that if you found a website that you could access by an IP address that had no external links that you could access it quickly, and that the delay you see is caused by other links within the page trying to do DNS lookup, which is failing. For example, if you try to bring up the router's internal configuration software "website" by putting 192.168.1.1 into the browser, you should get a response quite fast. This confirms the previous belief that there is a DNS problem.


I have yet to talk to the router's owner about a firmware update.
With regard to doing a full reset with the recessed button, what will this do that power off and on again wouldn't and how is it likely to affect other users?
I didn't realize that it wasn't your own router and you are correct and show the proper restraint in working with the owner. I'm suggesting the reset because we already saw that there was a problem with the router and it behaved differently the last time it was powered up. It seems pretty apparent that it isn't getting something about DNS right (even though it seems to get it right for Windows, which does puzzle me). A reset of the router may or may not resolve it, but if resetting is the fix then you could waste weeks or more fighting other things if I failed to mention this. As to the impact; absolutely work with the owner. Here's what the reset is likely to impact: if the owner needed to put user name and account information into the router, this will need to be done again. I have to do this for my router so that I can log into my DSL system, but my friends with cable connections do not need to do this. Also, if the router had to be configured to match the MAC address of the original computer, this will need to be done again. I've never had to use this feature on any system I've configured, but it's said to be needed by some cable systems.

Additionally, if the owner has configured any router rules, they are retained during a power cycle but will need to be re-entered after the reset. This might include limited time of day access for some systems, or special port forwarding for servers, file sharing, some games and things like VoIP telephones over the Internet. But the owner should know what changes have been made and need to be made again; beyond this there should be no impact on other users after a reset. See the owners manual for exact details on how to do the reset.


I was going to try using netcardconfig, saying "no" to the dhcp question and entering the information provided by ifconfig but netcardconfig asks for a Gateway address as well as an IP, Bcast and Mask. ifconfig doesn't seem to provide this. How would I get it or should I just use the default Gateway?
Yes, you should be able to answer no and do the manual setup. The Gateway, assuming that your not using a strange proxy or other complex setup, will be the router's address, which I expect is 192.168.1.1. If the mask is 255.255.255.0 then the broadcast address for that router address is 192.168.1.255 (it's always the highest address in the IP range as determined by the mask). You should be able to give the same IP address that you had in ifconfig, or better would be to use an address that is in the router's range but is not being handed ou by DHCP. In this case it looks like the router is starting to hand out addresses at 192.168.1.100, so the address 192.168.1.90 (for example) would likely be an address that the router has not handed out and will not give to another user later. You should be able to see and confirm the range of DHCP addresses from the router's setup pages to be safe.


Please keep us posted on your progress. The reset might not resolve the DNS issue, but I'm not sure where to turn next at this point and with the limited information we have so far as to what else would be the problem. But this is certainly an issue that can be resolved.

[David L.]

It seems pretty apparent that it isn't getting something about DNS right (even though it seems to get it right for Windows, which does puzzle me).
I didn't make clear earlier that while the Windows XP user is using the option to "detect settings Automatically", the DNS IPs are still entered manually on a separate tab within the Network Connections dialog, so the router isn't really "getting it right for Windows".

Thanks for the info on how to configure netcardconfig without DHCP.

I will be away for two weeks but hope to make progress with this issue when I get back.

[David L.]

I have succeeded in connecting to the internet using a static IP address i.e. saying "no" to the DHCP question and configuring the network card with the numbers you suggested above. URLs work fine so I find this solution satisfactory. Thanks. :D

[Harry Kuhman]

I didn't make clear earlier that while the Windows XP user is using the option to "detect settings Automatically", the DNS IPs are still entered manually on a separate tab within the Network Connections dialog, so the router isn't really "getting it right for Windows".
Many routers have the ability to enter the DNS servers that you wish to use in the router. And they will show you what they are using and handing out for use. I suggest that you check what your is handing out on the setup page. If it's different than what you find you have to use that would explain why Knoppix gets unacceptable settings by DHCP. If you can change this in the router (a feature that is unfortunately missing from my Dlink DL-514), then you could make the change once there and not have to do it manually every time you boot a Live CD or DVD, or every time you have to reinstall Windows.