I'm a Penguin, She's a Fruit

February 28, 2008 7:39 AM

Parallels and networking.... am I wrong in how I _think_ it should work?

My wife uses Macs at work, and lately she has begun to have to use WinXP in Parallels to get some stuff done. I am a linux guy/programmer, and frankly my Win experience is minimal at best. I know in VirtualBox and VMWare, (in the rare instance I run either/or) the easiest way for me to get networking working correctly, was to use bridged networking, where the Win VM would just use whatever connection was created under the hostOS for it's networking.
This allows me to bring up the network normally, including VPN if needed, on the host OS, boot the VM image, and go about my business. As far as the everything was concerned, I was on a network using one MAC and IP.

On wifeHawk's MBP, weird things are happening:
If she is at home, using the wireless, her host connects to the network, then she has to bring up VPN in the VM image to get work done. If she brings up the VPN on the host, it doesn't allow her to get on the VPN network. As I am writing this, it occurs to me, I am assuming that she does NOT bring up the wireless connection under the VM, as I didn't think that was possible.. but I am not sure.


If she is at work, networking on the VM doesn't seem to work at all - either through the CAt5, or through wireless.

Reading a bit on Parallels, it seems as though the CAT5 problem may be due to the VM attempting to get a second IP with a second MAC? i.e. the VM is trying to look like a second computer completely?

I am looking for advice on how it should be set up, and/or if my assumption that it should work like the other VMs I've used (NAT/Bridged networking in the guest OS to use whatever connection the host is using).

Any help would be appreciated - she is a Mac girl through and through, and if she cannot get this to work correctly, she will be forced to use a XP/Vista notebook 100% of the time, which is not on her favorite things to do list :-)

posted by niteHawk to Computers & Internet (5 answers total)

Parallels has both a bridged and NAT mode. In a bridged mode, a VPN client running on the host obviously isn't going to help the guest, so you'll want to make sure the guest VM is configured to use the NAT mode.

"bridged networking, where the Win VM would just use whatever connection was created under the hostOS for it's networking."

Your understanding of what bridged networking is turns out to be incorrect. Bridged networking means that the guest VM can inject packets directly onto the wire (or air, in this case) using something similar to TUN/TAP and it will make no use of the host's network configuration whatsoever. What you're talking about is a NAT configuration where the guest VM uses a NAT process on the host to take advantage of its network.

At the VM to be NATted and you'll most likely be fine.
posted by majick at 8:01 AM on February 28, 2008

Is it Cisco VPN or the Windows VPN?
posted by fusinski at 8:01 AM on February 28, 2008

was to use bridged networking...I was on a network using one MAC and IP.

Bridged networking allows the VM to function as a separate machine, with its own IP address. In shared networking the host receives an IP from the network and the VM receives its IP from the host. Configuring the VM with shared networking should do the trick. You should be able to change that option on the VM before you boot it. Then let the host do all of the network managing (like VPN etc.).
posted by Silvertree at 8:04 AM on February 28, 2008

Response by poster: ugh - you all are correct - I was using the wrong term - for some reason I keep thinking Bridged = NAT.

So, if we set Parallels up for shared networking, do we need to do anything internal to the VM once booted to let it know what is going on?

Thanks all!
posted by niteHawk at 8:18 AM on February 28, 2008

The guest VM being NATted should be configured as a DHCP client. Other than that, you're golden.
posted by majick at 8:27 AM on February 28, 2008