Hair pullingly frustrating network problem

[Quirrel]

I currently am using SuSE 10.2 but am in the process of testing out Mint for a replacement to SuSE due to the following networking problem.

At home I have no problems either connecting to the wireless network or plugging into my router via cable. everything is fine.

At work on the other hand I have the same problem with Mint as I do with SuSE. I have asked SuSE gurus to help solve it but none of them have come up with an answer yet.

My windows laptop at work plugs into the network fires up and connects everytime. No problems with network printing or access to the internet.

My Thinkpad however is another matter. It connects do problem to the network. Talks to the DHCP server gets it's IP address and lets me browse the network drive and print on the network connected printers.

It however does not let me get outside of the network.

Sometimes it does though. I can leave the cable in for 5 minutes and it connects to outside, sometimes it takes 20 minutes, other times it just doesn't.

I have tried restarting dhcpcd and dhclient. I have tried connecting the cable after it has started (sometimes works).

What does work everytime though is to plug the network cable into my windows machine. wait for it to connect and get it's IP. Pull the cable from the machine and plug it straight into the Thinkpad where it connects to the network and gives me access to the internet.

It's not an ideal situation to be in having to power up my windows box and plug and unplug cables just to get online.

I have tried KUbuntu, Ubuntu, Mint, KDE Mint, SuSE 10.2 and they are all giving me the same problem.

I like Mint. I like the completeness of the package and would like to use it full time, but I need to find a solution to this problem.

Any ideas as to what the problem is?

[Boo]

The problem may have nothing to do with Linux.
maybe it is not the laptop and linux distros maybe it is the router or some other network service/config that is stopping you.

your desktop could be using DHCP but is given static IP for its MAC address or for that port on the router and given MAC.
before getting too technical and dreaming up crazy networks you could do some testing and give us some more info.

MAC addresses of the laptop and desktop?
use you working work around:
when you boot the desktop first, get its IP address.
then when you move the network cable to the laptop, get its IP address.(ifconfig-a)

you could also look at the IPs with the other non-working methods you use.

scorp123 may also have some crazy ideas too.

[Quirrel]

Both machines are laptops (doubt that matters)

Ip address for windows - 172.31.10.30
MAC dunno.


IP Linux - 172.31.10.34
MAC - 00 16 D3 2E A9 76

Both are using DHCP, prior to SuSE I had win XP pro on my Thinkpad. No problems connecting to the network.

I have the kill switch on for my wireless adapter . I have had more success with it on than off.

I feel pretty stupid at work having to fire up the windows lappy then whack the LAN into my one to get onto the network.

The thing is that I can access the network on both machines it's just that the Internet isn't available on the Linux machine unless I perform my cable swapping trick.

[Boo]

sounds like some crazy proxy problem.
or maybe a gateway one. could be dhcp related.

does your work use a proxy?
if so have you set it up in firefox and preferences-->proxy settings?

but still the cable swapping solution makes no sense for proxy unless...
you need a better network guy than me.

have you tried leaving the work laptop on and networked while your off else where and when you come back swapping and booting?

now I'm just making up all sorts of scenarios for testing.

[Quirrel]

You have just made me remember one scenario where it worked.

One of the network management programs has an option on it to automatically detect proxy and that worked. I can't remember what distro it was on or what network manager it was.

Any ideas?

That was three weeks ago the day before i went on vacation so I didn't pay much attention.

[scorp123]

One of the network management programs has an option on it to automatically detect proxy and that worked. I can't remember what distro it was on or what network manager it was. Any ideas?

Sorry, our crystal balls are out for repairs and I am not good at Tarot cards ... but maybe Boo has improved on his palm reading skills? Can you please send us a picture of your hand palms? Maybe the layout of the lines will tell us more. I will also tell my secretaries to dance around naked ... this usually is quite inspiring for us admins here and we then come up with tons of "fresh ideas", some of which even include Linux ....

Just joking.

Seriously ... you will have to give us more precise details please.

[scorp123]

At work on the other hand .... My windows laptop at work plugs into the network fires up and connects everytime. No problems with network printing or access to the internet.

Was that Windows machine issued by your employer? And was it configured by your company's IT division? That would explain a lot ...

Where I currently work the use of non-company computers on the company's network is strictly forbidden! They even have MAC-filters ("MAC" here means "Machine Access Code"; the low-level hexadecimal hardware address of your network interface) so that non-approved PC's that someone tried to plug into the network can't get anywhere and don't even get a TCP/IP address ... Instead any attempts to get into network would trigger an alarm and a security team will show up in no time. There are switches under each group of desks ... so the alert log will tell them from which group of desks the connection attempt originated (because they are all connected to the same switch).

Even if they don't have such strict security measures at your work place I suggest you be cautious with these things and get approval first to really make sure you don't run into any unpleasant troubles.

I'd check with your company's IT division if what you are doing there is even allowed? Plugging your private laptop into your company's network can cost you your career otherwise. And if they ever find a virus in the network they can blame it on you and then sue you for damages ... Even if you are not in the USA where they can easily seek millions from you it could get very expensive.

Any ideas as to what the problem is?

Sounds like they use NTLM authentication for all their connections. Is your Windows machine a member in their domain? Do you authenticate via a Windows domain controller? There you go. Besides I seriously doubt you're supposed to plugin your private equipment into your company's network ... see above. If they wanted you to do that they'd implement simple "out of the box" standard DHCP and not bother with such things ...

[Husse]

Scorp123 is right - you may not be allowed to use your own computer in the company net.
But if you are the "trick" described here may help you
http://www.linuxmint.com/wiki/index.php ... or_envy.3F

[Boo]

I can see 2 possible readings of your handy work.

1. using a manual network configuration
general tab, tick the "Automatic service discovery"
this may automatically detect your proxy settings.

2. menu-->preferences--> network proxy.
proxy config tab.
now if you know the manual proxy settings you can enter them.
your network may use an automatic proxy config so use the bottom one.
you may or may not need the url, just test it with and without.

more things to try...

[Quirrel]

Yeah it was KUbuntu that had the auto proxy option

I will check it again tomorrow.

Sadly the time difference makes it harder to work on.