Host only networking fails to pass traffic.

[Perkins]

Ubuntu 9.04 host.
Virtual Box PUEL 2.2.4 r47978

NAT networking is fine.
Bridged networking is fine.

Host only networking:
Host can ping its own address on the host-only adapter.
Guest gets a DHCP address and can ping itself.
Guest pinging host receives no response.
Host pinging guest gets the following error message: "ping: sendmsg: Operation not permitted"

I am not able to find any advice on this either on google, or these forums. Has this happened to anyone before? Or have I stumbled across a unique configuration?

[Perkins]

As usual, I have a brainstorm 30 seconds after posting and fix it myself.

Apparently, with this install, /dev/vboxdrv has rw permissions only for root. I had looked at it earlier and seen that it was in the vboxusers group and assumed that it was not the cause of the problem.

I changed the permissions to 660, and host-only networking now functions properly. Would I be correct in thinking that this should count as a bug?

[Perkins]

Ok, so it's only half fixed. With the permissions change I can now ping the host from the guest. However, I still get the same "operation not permitted error" when attempting to ping the guest from the host.

Running the ping as root doesn't work either.

[Sasquatch]

The privileges on my system for /dev/vboxdrv are crw------- root vboxusers. If that is not the case on your end, then you might want to recompile the module (sudo /etc/init.d/vboxdrv setup).

[Perkins]

Those are precisely the permissions I had. And they are what it gets set back to on a reboot. Changing them to crw-rw---- made it partially work temporarily. I have since rebooted, and now even that change doesn't work. So there must be something else I'm missing here.

Recompiling the kernel module makes no noticeable difference either.

[Perkins]

AHA! Oh that helpful little firewall program which decided that since it can only configure one interface, it should block *all* traffic on the others... I am pretty sure it's not supposed to do that... So now I get to go bother somebody else for a while. Thanks for the help.

[Sasquatch]

Let me guess, firestarter? It's been a real PITA on my end too once. I quickly discovered the problem. It asked me which NIC I use for internet, gave it and it shut down any traffic on my peer lan between my PC and laptop.