I have VirtualBox installed on two machines. On the one machine the virtual machines have access to the internet. On the other they don't. I didn't configure a network bridge on either machine. The only significant things that are different are the motherboards and the kernels. The one that has access has a later version of 2.6.27. Any ideas why the one just automagically works?

There's a dozen different reasons that could cause this. When you say it doesn't have access to the internet -- does it get a virtual ip (usually 10.0.0.0/8 netblock) from the host? Can you resolve IPs with dig or host? Are there any firewall rules in place on either box? Is either box multi-homed (multiple network connections)? What guest OSes are you using? Are you using NAT for networking on both?

Let me start all over. Both host machines are running Lenny with custom kernels. The kernel configs are almost identical on both kernels. The guest OS on both machines is Windows 2000. Both machines have Atheros AR5212 based wifi connections with wpa_supplicant and dhclient3 on the ath5k driver in the kernel. The VirtualBox software on both machines was downloaded from source. One was compiled with kmk. On the other, the one that doesn't access the internet, I have tried both compiling with kmk and with fakeroot (the debian way). Running netstat -r on both guests (both machines) shows an ip address of 10.0.2.15. The routing looks the same on both. The /etc/network/interfaces files are the same on both machines with the exception of different static addresses on the ethernet cards joining them together this side of the ATT router. Both guests use the default network adapter with NAT. There are no firewalls in place. In both guests, nslookup tries to go through 10.0.2.3. One works, the other doesn't.

That's kind of jumbled, I guess. Sorry. But it does pretty much describe what's going on. I have no compelling reason that these need to work. It's just a toy to play with for a few days till I get bored with it.

Matir, in case you see this, the problem went away. Now the guests on both hosts have internet access, and I didn't change anything that I can see, other than a kernel recompile. This is Lenny, though, so maybe it was some update that one got and the other didn't till later? I dunno.

And, now, the system doesn't have access to the net again. I have no idea on this one. Any ideas would be really appreciated.

This is perhaps beyond my ken but if vbox intermitant in it's web conection then maybe those details were being placed in the RAM and not on the 'hardrive'? Virtualisation does appear to be heavy on ram and however clumsy this may appear, anything to help.

Fred.

Hi Fred. Sorry not to respond. I think I've traced the what down, but not the why. On the one that had been intermittent and then just stopped working: after trying a tap hooked to my wireless to no success (https://help.ubuntu.com/community/Vi...s%20Networking), I went back to NAT and manually set the gateway IP in the Windows Guest. It's been working reliably since. Why the other host machine didn't need that step is beyond me. I had tried this before but had mistakenly though I needed to have an IP in the Guest on the same subnet as the Host. When I left the Guest IP at discover automatically and set the gateway IP manually it worked fine.

cheers!