virtualbox.org

Here's an interesting one:

I have a Vbox setup:

Intel Quadcore 660:
4GB RAM:
500GB Sata HDD:

Network: Linksys wrtg54 acting as DHCP server

Vbox: 1.6.6
Host: Ubuntu Desktop 8.04.1
Guests: Ubuntu Server 8.04.1 (with ubuntu gnome UI installed), Mythbuntu 8.04.1

Networking is set for DHCP (static IP addresses are not really desirable in this build). Bridging and TAP setup seems to be working so far. Both guests grab a DHCP correctly on the first boot. However, if the guests are rebooted, only the Mythbuntu guest gets refreshed. The server guest fails to get an address.

Watching the DHCP section on the Linksys router, the server is trying to get an address but it never gets issued. Watching the guest (server) boot, the screen shows the trying to get an address but it times out.

An ifconfig on the server guest shows only the loopback interface with an address. ETH0 has no address. The mythbuntu guest gets an address every time.

The only way to resolve the issue so far is to bring down the TAP interfaces and restart networking which is not really practical, nor desirable

Can anyone shed some light on why?

Thanks.......

You use a wireless router, do you also connect using wifi? If so, then there is your problem. Bridging and wifi don't work correctly. You should be lucky that it actually gets an IP address in the first place.
If you use a cable however, this is quite strange. And why isn't static addresses an option? If you set it properly, you won't have any problems (I have static addresses in my XUbuntu desktop system on bare hardware running just fine).

Hi,

I'm not using wireless for the VMs (or the hosts) connection. It is purely a wired network. All PC's connected to it use the same DHCP server in the router as discussed in the original post.

The DHCP addresses are statically bound (i.e. the same address gets dealt out, based on the MAC address of the requesting device). There are 4 other systems using this capability and all others work great. The only one affected is the virtualised Ubuntu server 8.04.1. All other VM's are getting their addresses fine.

See if you happen to have a duplicate MAC address in your network. The chances are slim, but still possible. Also, what does your router's log say about the DHCP request? Does it pick it up at all?

Checked for duplicate MAC addresses and didn't find any. MAC addresses for VM's are generated by VBOX. router does not have duplicate MAC addresses in the static DHCP allocation table.

As far as what is seen by whom;

The router sees DHCP request, only when the the VM's network config is changed from static to DHCP and it indictaes that it has issued an address but the VM never picks it up.

If the VM is set for DHCP and after doing a network restart, the VM console shows it reqesting an address, but it thinks it gets no response. Watching the router at the same time shows that the router is no seeing the DHCP request. (i.e it deosn;t seem to be getting out of the the VBOX environment.

further t/shooting info;
Restarting the TAP interfaces is not working any more and I had to restart the host to even get static addressing to work. Mythbuntu VM is still working OK. Server VM will not hook onto a DHCP and is now running static addressing.