Bridged networking problem

[electricart]

Hi all.

I'm having a strange problem with Bridged networking on my MacOS X 10.7.5 host running Virtualbox 4.2.10r84104.

VMs that I create and set to Bridged networking on my MacOS host will talk to other physical machines on my network, but will refuse to talk to other Bridged networking VMs, either operating on the same host, or operating on an another Virtualbox host on the same subnet (running Solaris 11 and Virtualbox 4.1.14r77440). If I set the VM on the MacOS host to NAT, it can see the other VMs on the MacOS host or on the Solaris host fine, but with Bridged it doesn't work for some reason. I need these VMs to run as Bridged, as they are servers, and have permanent IP addresses.

The Solaris VMs are set to Bridged as well, and each is Bridged to it's own VNIC. The Solaris hosted VMs also can't ping the MacOS hosted VMs - so no communication both ways.

I read about some potentially similar issues with Bridged networking on MacOS hosts, with some people suggesting to run the command (on the MacOS host):

Code: Select all

sudo sysctl -w net.inet.ip.forwarding=1

However this did not work for me. I also tried changing the virtual hardware for the NIC to AMD PCNet PCI II (Am79C970A), as this was also suggested, however this did not improve anything either.

Is this expected behaviour and I'm just missing something obvious? Apologies if so. I would think that this should work, and am stumped as to why I can't get it to work. Any help on this would be greatly appreciated!

[noteirak]

I fail to understand your actual setup, because some of what you say don't make sense : it is not possible for the host to see VMs with NAT interfaces, since the subnet only exist in Virtualbox. You must have another interface bridged or host-only to see them.
You talk about two hosts : what about the subnets used? What about firewalling? How are the hosts connected to each other? Via a simple switch?

If you could provide :
- a network map of your setup with IPs and equipement, that would help.
- list of interaces and their IPs on the hosts & on one of the VMs on each host
- routing table of your hosts & the said VMs
- config of the said VMs using : vboxmanage showvminfo %vmname% --details