Bridged networking with MAC-access-control

M

MalteB

Bit poster
Hello all,

I am new to Parallels' networking features and am having trouble getting my Ubuntu server to both have access to the network and be accessibly via the network. I understand that the former can be accomplished by shared networking. To have the latter work, however, bridged networking is required.

Our network admins granted me two IP numbers each with a specific MAC address. My Mac (10.6.4) is able to access the network and can be accessed by other machines. The Ubuntu server on the image, however, cannot be accessed.

Details:
In Network preferences, I set up Ethernet Adaptor (en4) with the required IP address and configured the Parallels image running Ubuntu server to use bridged ethernet -> (en4). When I try to ping other computers, I get "network is unreachable". Perhaps I should also mention that I have one ethernet cable going into my MBP.

What I noticed is that in my OS X network preferences, the MAC address of the Ethernet Adaptor (en4) is set to 0b:0b:0b:0b:0b. Changing/spoofing the ethernet ID doesn't seem to work easily on OS 10.6.

Any idea why I might not be able to connect to the network using my bridged ethernet solution?
 
Strange that your Ethernet Adaptor is en4. I would expect it to be something like en0.

Are you using Parallels Desktop 5? It doesn't show the Unix adapter names like en4. It shows the names that you see in the Network preferences panel of System Preferences. The names shown there can be matched to the Unix names using "ifconfig -a" in a terminal window and matching IP addresses.

The way to setup bridged networking is to find which network adapter you are connected to (see 1st picture - I'm connected to Ethernet 2) then use that for the Bridge Networking adapter of your virtual machine (see 2nd picture - I choose Ethernet 2).

The MAC address of the Mac's ethernet adapter is changed using something like this:
sudo ifconfig en4 lladdr 00:e2:e3:e4:e5:e6

The MAC address of the virtual machine's network adapter is changed in the network adapter settings (see 2nd picture).

Changing the virtual machine's network adapter while it's running instantly makes the change in Windows I think. But for Ubuntu, I have to select Disconnect first, wait for the "Disconnected - you are offline message", then select Bridged or Shared or Host-Only to reconnect, and wait for the "Connection Established" message to appear. Then "ifconfig -a" in a Ubuntu terminal window will show the change.
 

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Hi Joe! Thanks for your post. I hadn't realized that there was an Ethernet and and Ethernet Adaptor. I just added an Ethernet 2 service in my network preferences but apparently cannot hook the Ubuntu image up to Ethernet 2 (see attachment).

On another note, assuming I was able to add Ethernet 2 to the list, the Ethernet ID of Ethernet 2 is the same as Ethernet 1. I know that I can assign an ethernet ID to the image but will that overwrite the ethernet ID in network preferences? The company router will only allow me to access the network if I got the right ethernet ID.
 

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Don't add services to the Network system preferences panel. I have services called Ethernet 1 and Ethernet 2 in my setup because my Mac Pro has two Ethernet connectors. What kind of Mac do you have?

Anyway, from your screen shot, it looks like you're connected to the network using AirPort (it has the green light and says connected in the Network system preferences panel). Therefore you should choose Airport for Bridged Networking.

Click the (?) button in the virtual machine network adapter configuration window for more info. If you're connecting with Airport then there's a section called "WiFi Bridging Support" that may be relevant.
 
Pardon, my screen shot is a little misleading. I took that one at home, there is no wireless in my workplace. I have a MBP with one ethernet port. The MAC-address-filtering at my workplace is activated to prevent people hooking up their private laptops. Putting the MAC-address issue aside for a minute, can I do bridged networking over one ethernet card?
 
That's what bridged networking is for. It makes your one ethernet card look like two or more. A single ethernet card can listen to traffic sent to multiple IP or MAC addresses. For example, my MacPro is connected to my router with a single ethernet cable. However, with two virtual machines running, my router sees three computers:
Code: 
192.168.0.190  joevt-Ubuntu1  00:1c:42:64:d0:3b
192.168.0.191  JoeWindowsXP   00:1c:42:9c:45:dd
192.168.0.193  JoeMacPro      00:1f:5b:39:c8:bd
Leave the Mac settings alone in the Network system preferences panel, and just setup the network adapter in the virtual machine configuration to point at your Mac's connection.

The network adapter settings in the virtual machine tell which network connection to use and what MAC address the bridged connection will have (which should be different than your Mac's ethernet MAC address). Then you set the IP address in Ubuntu.
 
Hi Joe!

Thanks for pointing this out. I have gotten it to work.

A friend pointed me to "/etc/udev/rules.d/70-persistent-net.rules" where I found 3 entries with the same PCI device address., subsystem, action, and drivers, etc. What differed though was the ATTR{address} and the NAME (eth0, eth1 and eth2). It was eth1 that had the MAC-address that I wanted. So I simply commented out the first line (eth0) and restarted the Ubuntu image.

I set my static IP address following the instructions in this article.

Thanks again for your help and patience, Joe.
 
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