dual boot, XP loses DHCP connection after system boots into Linux

[john2k]

My setup:
- Primary Master HDD: Windows XP
- Primary Slave HDD: White Box Enterprise Linux (RHEL 3 clone)
- ASUS A7N8X Deluxe motherboard
- Linksys cable router

Using Grub to dual boot the system with Windows XP on the master hdd and Linux on the slave drive. It seems that whenever I boot the system into Linux and then back into Windows, the Internet connection is lost in Windows XP but still works when I boot back to Linux.

For example, if I'm using WinXP with the Internet connection (via the cable router) working fine - after I boot to Linux (where the Internet works fine) and back into Windows I lose the Internet in Windows. If I boot back into Linux the Internet still works there, but not when returning to WindowsXP.

To get the Internet working again in WinXP it usually takes a few reboots and removing that particular computer from my DHCP table in the cable router.

Going back into Linux even once causes the same trouble all over again.

My motherboard is an ASUS A7N8X Deluxe and I use the 3COM ethernet port to connect to the cable router. I use the same hostname for both the Windows XP installation and the Linux installation.


How do I make it so that both Windows & Linux use the same ethernet adapter without having to go through so much hassle getting the Internet back up on Windows each time I boot from one to the other?

[madcompnerd]

Maybe there is something wrong with your cable router?

[john2k]

I have 3 computers hooked up to the cable router, including the WinXP/Linux box. The other two WinXP computers have no problems with Internet connectivity, even when the WinXP/Linux box is having problems.

[JohnT]

I use SBC adsl and if I don't disconnect before leaving windows I have to re-set the modem or it will not connect in Linux until I do, but not so when leaving Linux which does a clean shut-down of the connection when leaving. its Windows and the equipment......not a bug.

[madcompnerd]

If he is right you can just go in and disable your connection in windows before rebooting. It's in network properties.

[JohnT]

Its actually easier just to right-click on the icon in the system tray and choose disconnect from there.

[XiaoKJ]

if you like to do it physically, just unplug and plug in the ethernet cable...

It should just be a case whereby damn M$ windows can't refresh the DHCP lease...

[john2k]

Does this mean that everyone who dual boots WinXP & Linux has this same problem?

WinXP & Linux cannot share the same ethernet port when in a dual boot configuration without causing a mess each time when booting between the two operating systems?

[Takaznik]

does it pull down different ips every time you reboot?

ie when you boot into windows teh first time you get 192.x.x.1
then linux gets 192.x.x.2
then windows tries to get something else?

if so it could be that your DHCP clients table is too small and doesnt want to give you enough ips

[mdwatts]

Moved to the Networking forum since Installation is meant for distro install issues.


Linux Install Help: Need help installing your Linux OS?

[XiaoKJ]

Originally posted by john2k
Does this mean that everyone who dual boots WinXP & Linux has this same problem?

WinXP & Linux cannot share the same ethernet port when in a dual boot configuration without causing a mess each time when booting between the two operating systems?

no -- my router runs just fine...

and that symptom occured on a winXP only system... and I couldn't renew lease so I did the unplugging...:D

Cracks...

[john2k]

Both WinXP & Linux are assigned the same IP address by the router. 192.168.1.101

Initially, the WinXP computer name / hostname and the Linux hostname were exactly the same. I thought that maybe they needed to be since they use the same ethernet port.

After I noticed the problems I changed the Linux hostname in /etc/sysconfig/network to see if that would make any difference. That didn't seem to help any.

[XiaoKJ]

domain? workgroup?

I think this isn't a configuration thing -- it should be installation thing. I suspect your windows installation was messed up...

[john2k]

workgroup

Didn't have any problems with my Internet connection on WinXP until after I installed Linux and booted into that OS on the other hdd.

[john2k]

Would the hostname have anything to do with this problem?

When dual booting WinXP & Linux, should both operating systems use the same hostname or different hostnames? Does it even matter?

[JohnT]

The problem is with the equipment (modem) + XP. Your ISP probably gave you a cd to load with a tool to do this for you, but if your like most why bother when XP can be set-up with adsl with its inherent software. You have a choice either use the software your ISP gave you or disconnect with a right-click on the icon. This should not be a difficult concept.

[john2k]

My cable router is configured for my ISP and my individual systems are configured to access the network through the cable router (which handles the connection to the ISP). I can access the Internet & local network from my other computers - no problem at all (both Windows & Linux systems).

With the particular system that I'm having trouble with, there were no network/Internet connection problems before I installed Linux on the second hdd.

My broadband connection is cable, not any form of dsl - so there isn't any need to manage the connection with a dialer. My network connection is always on. There's no requirement from my ISP to ever connect/disconnect.

I don't see why the network connection can work perfectly in WinXP for hours, then stop working as soon as I boot into Linux then back to WinXP a single time.

Something appears to be happening to the configuration of either the cable router or the ethernet port when I boot from WinXP to Linux and back again.

Here's what typically happens:
1. System is booted into WinXP for several hours. Could even be turned off and back on a short while later during that time. I've even tested with multiple concurrent reboots. All the while there are no problems with the network connection.
2. Turn off WinXP and boot the system into Linux (using White Box Enterprise Linux, clone of RHEL 3).
3. Internet connection works fine while in Linux.
4. Shutdown Linux and boot system back into WinXP.
5. Back in WinXP, network connection lost

My guess is that during #4 above something happens that causes WinXP to lose network connectivity when it boots up.

I don't know exactly how cable routers work - but I figure that the assigned IP address in the router's DHCP clients table is bound to either the mac id of the ethernet card or to the hostname of the OS. Maybe a combination of the two.

Should the hostname of both the WinXP & Linux installs be the same, or different? Does it matter?

Is a DHCP connection any different between WinXP & Linux when on the same exact hardware & network?

Does the cable router simply need a few minutes to reconfigure the DHCP connection for WinXP after it's used for Linux?

Any other possible causes that I should look into?

[JohnT]

See if your assigned address is the same in each OS while connected. In Linux it would be found using "ifconfig" then look to your "ppp0" section. In XP just right-click on the icon in the systray and choose "statistics" (something of that nature).

[john2k]

Just checked. The assigned IP address is the same in both WinXP & Linux, when the network connection is working correctly (192.168.1.101).

I also just had a look at this same data when network connectivity is lost. This is exactly what I did when first booting up the computer:

1. booted into WinXP, network good
2. booted into Linux, network good
3. back into WinXP, network still good
4. booted back to Linux, network good
5. booted into WinXP, network LOST
6. booted back to Linux, network LOST
7. boot back to WinXP, network good
8. boot to Linux, network good
9. back to WinXP, network LOST
10. reboot WinXP, network good

When network connectivity is lost in WinXP, the IP is 169.254.112.241, subnet changes to 255.255.0.0 (from 255.255.255.0) and Gateway & DNS are blank.

When Linux loses connectivity, ifconfig does not display a section for eth0. During bootup, "Bringing up interface eth0" [failed].

Something else I noticed while checking this info in WinXP, whenever the connection is re-established in WinXP after being lost, the DHCP lease is obtained time changes to be close to the current time (the time of that most recent boot up).

My Linksys cable router is configured for a DHCP client lease time of one day. When I first booted WinXP the lease obtained time was from last night. After the WinXP connection was lost & reobtained, the DHCP lease obtained time was the time of the most recent boot. Same happened after the connection was lost & re-established again - lease obtained time updated to most recent boot time. The lease expiration time always remained at 24 hours after the lease obtained time.

[JohnT]

Is your eth0 being modprobed at startup? If not look in /etc/rc.d/rc.modules to see if it's listed, then uncomment it.

[AdamZ]

How many addresses is your router configured to hand out by DHCP? If it's only one, try changing it to 2 addresses. That might fix the problem.

[john2k]

I don't have an /etc/rc.d/rc.modules file on the system. Nothing that even looks like it in the /etc/rc.d/ directory. "locate rc.modules" found no files by that name on the server. I'm using RHEL 3, maybe rc.modules is under a different file name on that flavor of Linux.

In my cable router DHCP config, there's a field for "Number of DHCP Users." I have that set to 50, although I only usually have at the most 3 or 4 computers hooked up to it.

[JohnT]

In my cable router DHCP config, there's a field for "Number of DHCP Users." I have that set to 50, although I only usually have at the most 3 or 4 computers hooked up to it. Try setting that to number of "actual"users.

[john2k]

I set the # of DHCP users to 3 and booted between WinXP & Linux a number of times.

Linux -> WinXP -> Linux -> WinXP -> Linux -> WinXp -> Linux

Second time I booted into WinXP the network connection was lost, the boot into Linux right after that also lost the network connection. Then WinXP re-established the connection (3rd boot into WinXP) with a new DHCP lease obtained time. Network connection also worked on boot into Linux right after.

[Alex Cavnar, aka alc6379]

Why not just set a static IP in Windows?

That'd eliminate fooling with all of the DHCP renewing/releasing garbage that may be occurring...

[john2k]

That was the next thing I was going to try... static IPs in both WinXP & Linux. I suppose I can still use DHCP on the router while using static IPs on the one system...? I'll know soon.

[XiaoKJ]

what i would suspect is that there is a firewall on your XP system that blocks new connections.

on my brother's laptop, I had installed zone alarm and I set the setting to be quite normal. however, it would block DHCP and then it would not connect to 192.168.10.0 and I had to manually set the system manually configured alternative to 192.168.10.20 and it would connect.

Thus I suspect the same for you and the DHCP lease went down while the firewall was up, therefore you cannot connect with DHCP.

I suppose unpluging and repluging is best :D

[john2k]

I use the firewall that comes with WinXP on all my WinXP systems. I have 3 other systems that are WinXP only, no problems at all with the cable router & DHCP on those systems.

[john2k]

Update...

I've tried static IPs in both WinXP & Linux on the dual boot system, still ran into problems. The IPs were different as well as the hostname. I'll try this again with the same hostname in a few.

Also updated the firmware on my cable router... that didn't seem to help much either.

[john2k]

Just wanted to update this thread for anyone who was following it:

After trying many different configurations I was still unable to get WinXP & RHEL 3 to connect over the same 3COM integrated ethernet port in a dual-boot config. While researching I did come across a website with information relating to this issue - that site mentioned that the dhcp client on the Linux OS could cause some problems if it is not fully compatible with the WinXP dhcp client. That site recommended a specific dhcp client that is known to be the most compatible with the WinXP dhcp client - so that both operating systems communicate with the router in the exact same way. A dhcp client communicating with the router in a way that is not compatible with the WinXP client might be responsible for issues with the router's dhcp lease that is assigned to the 3COM port. The focus was put on the Linux dhcp client because WinXP only has one dhcp client that it can use, while there are a number of dhcp clients that can be used on Linux. I did not change my dhcp client under Linux, btw.

To *bypass* this issue, what I did was setup WinXP and Linux to use separate ethernet ports on the machine. My motherboard (A7N8X Deluxe) has two integrated ethernet ports. Setup the Linux OS to use the 3COM port and WinXP to use the Nvidia port. Once that was setup, no further problems with net connectivity in either OS.

[JohnT]

Got a link to the site?