Trouble connecting to network via DHCPForum: Networking Topic: Trouble connecting to network via DHCP started by: Atreus Posted by Atreus on Feb. 19 2007,19:31
I am using DSL on my older laptop, and it works great. I have had no trouble connecting to wireless or hard wired internet at home, or at friends house.This inquiry deals with a hard wired ethernet connection. When I go to the University the laptop won't connect to the internet. They only provide tech support for windows, but the IT people said (for a windows computer) it should automatically connect via dhcp with no problems. The dhcp configuration (via dsl pannel) works great for every other network I have been on. However, for this network it just returns an error, after waiting for about 10-15 seconds. I have tested multiple ethernet cables and jacks, but get the same result. Anyone have any ideas? Posted by jeanspv on Feb. 19 2007,21:45
If you don't mind me suggesting two obvious ones: are you quite sure you are giving the right network name to the University network and are you ok with encryption?
Posted by roberts on Feb. 19 2007,22:03
Perhaps the University is using a proxy server?Maybe this will be < helpful. > Posted by Atreus on Feb. 19 2007,23:08
I'm not well versed in networking, so bear with meIn responce to jeanspv, I am not specifying ANY network name. Would I need to? The network is not encrypted. I have friends with mac/windows computers, and they simply plug in and go. No setup or login required. Posted by rja on Feb. 20 2007,04:44
Which version of DSL?Is it running from a live-cd or installed to a hd? Did you try the same jack and cable that worked with one of your friends computers? Try running: sudo ifconfig -a to see the network settings before and after netcardconfig What error message did it return? Posted by Atreus on Feb. 22 2007,15:04
Sorry for the delay, I haven't been able to test it out until today. Here is the info requested.Which version of DSL: I don't know exactly, my iso just says 'current'. It is using a 2.4.26 Kernel, and I downloaded the most up to date DSL version in December 2006. I am running on a 'frugal' hard drive install I am fairly certain the jack I am using works. I will test it again this afternoon with a jack that I am SURE works. I'll make another post with those results. Running Sudo ifconfig -a before
after running the netcardconfig
The error returned when running netcardconfig is:
Hopefully this helps. Posted by Atreus on Feb. 22 2007,17:37
Ok, this time from an ethernet jack that was confirmed to work 10 seconds before I plugged in.sudo ifconfig -a before attempting connection
After attempting connection
Error message was the same as before. Posted by WDef on Feb. 22 2007,19:34
University networks I have been on won't just let you connect any old laptop anywhere on the network - you have to get the Windows Monkeys to register the MAC address of your laptop in order to be able to get assigned an IP. Where I was this meant the laptop got blueplated with an id code, and even then I could only use it on a certain part of the network - my department.Machines with unrecognized MAC addresses simply could not connect via ethernet. This sounds like your problem. Do the Windows monkeys know about your laptop? if you are dual booting Windows, get them to set it up on the network running Windows. After that, booting dsl while hooked up will probably connect you. If not, you can run ipconfig in a Windows command prompt and write down the settings, then manually set these up in dsl with ifconfig. Put the name servers in /etc/resolv.conf if these are not already there. Posted by Atreus on Feb. 22 2007,21:02
I'll ask about the mac address, but last time I went in and asked about this, they seemed to think that it should just work without doing anything in particular.I am not on a dual boot with windows, and they will only provide support to windows. Posted by rja on Feb. 23 2007,02:13
It sounds like it should just work, so something odd is happening.My "carrier:0" from ifconfig stays at zero while yours is nonzero. Could it be a 10/100/1000Mbps missmatch? dmesg | grep eth If you still have the live CD (sounds like it is 3.1), try booting from that, in case something has messed up your frugal install. If that doesn't work, then try booting with some special cheatcodes. You can see what you normally use with: cat /proc/cmdline add on any cheatcodes that you need to this: boot: dsl dma base norestore syslog nodhcp edit: oops, maybe you don't want the "dma" cheatcode. Then, you can start a root shell and watch /var/log/messages to see what pump is doing with: [/home/dsl]# less /var/log/messages at another root shell: [/home/dsl]# pump or /home/dsl]# pump -v for more details. Posted by rja on Feb. 23 2007,02:27
Also, if you ask your network admins nicely, they might look at the logsfor their dhcp server to see if they are responding to your mac address when you run pump. If they do not see any requests with your mac address, then the problem is at your end. Posted by Atreus on Mar. 09 2007,01:57
And the plot thickens....I went and asked nicely when they weren't busy, and now I am even more confused. First off: The network is definetly open. Anyone can plug in and get on the internet. No configuration / login necessary So I plugged in at the tech office, on a port usually used by one of the guys there. I was ready to show them that it wouldn't connect. SUPRISE! It worked. I ran netcardconfig, and everything was happy. I was able to get on the internet and check email. I asked if anything had changed in the past week, and they said no. One of the tech's went then with me to the port I had tried to access before (from when I couldn't get on) I tried to get on the network and it wouldn't work. Same error as before. He plugged in with his XP laptop and it worked fine for him. At this point we were both confused. He said the 'public' port (the one that didn't work for me) used a different switch, but that was the only difference. I decided that further investigation was needed. I got a friend with an XP laptop, and a friend running Kubuntu and we went around and tested ethernet jacks. The kubuntu and windows laptop could get on the network at every port we tested. I was only able to get on the network on 'non public' ports. Just to reiterate: there is no configuration required. My friend with the Kubutnu laptop doesn't even attend the University. So is there a problem with the netcardconfig script? I tried it with the live cd but it made no difference..... Posted by ^thehatsrule^ on Mar. 09 2007,05:52
This reminds me of a time when I used some restricted gateway...This was a desktop, with some pci NIC - worked on modems, hubs, routers. However, upon using it on the gateway... (which I think used some cisco switches) it would hardly work at all. It seemed that this particular NIC brand was at fault with the particular switch. So I ended up grabbing some usb NIC, and it all worked out. This happened on windows and linux distros (on the same machine). If it's only your laptop that's not working - try connecting with another card. Posted by Atreus on Mar. 09 2007,13:04
Ok, I was wondering if it was a hardware issue. If I can find something cheap, I'll give it a shot.-Andrew Posted by rja on Mar. 12 2007,22:06
Sounds like the combination of your network adapter and that network switch are not working together.To see what kind of NIC you have, run: dmesg | grep eth The MAC address shows that it is made my 3COM. My laptop has a 3COM 3CXFE575BT pcmcia card (10Mbps), and it fails to connect to my cheap Netgear GS608 switch (10/100/1000) most of the time. After a few reboots, it will finally get a link. That laptop and 3COM pcmcia card ran DSL on an older Netgear 10/100 router for years without any network problems. A newer kernel module for that network card MAY be able to connect with the switch. You could try a livecd from a different distribution which has a more recent kernel. The latest KNOPPIX CD has a newer kernel. Posted by rja on Mar. 12 2007,22:17
If your friends with the XP and Ubunto laptops still want to help, you could try having them boot the DSL live CD from their laptops and see if they can connect to the network switch with their NIC's.That way, you can make sure that it is a problem with your network card/network switch combo and not with DSL. Posted by ben4dsl on Mar. 14 2007,21:38
I have had a similar experience connecting an older NIC to a managed switch. It seemed that the switch tried to autoconfigure the speed and would not correctly identify the NIC as only capable of 10 mbit half duplex so it believed the card was capable of full duplex. Nothing went through and everything got stuck.The solution in my case was to tell the switch to configure that particular port manually and set it to 10 mbit half duplex. A basic case of automatic sensing gone wrong (because of old, possibly slow, NIC). The reason the other port worked for you is possibly because it is another brand/model switch/hub managing that port. It could also be that you can modify your card to speak full-duplex or at a higher rate if it is capable of it. You could also try connecting a minihub/switch between your computer and the ethernet port. The intermediate hub will hopefully "understand" your NIC and it will certainly be understood by the network. Good luck. |