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So Sophos UTM (Astaro Gateway UTM) can be virtualized in Hyper-V, VMWare, vSphere etc. Now I'm new to virtualization, so am wondering how the networking would be configured in this situation.

Imagine the following (a very simple setup). A Zyxel router acting as the default gateway, standard ADSL line. This is connected directly via Ethernet to my VHost, Hyper-V in my case. Now I assume I need two virtual network adapters, one which is the "External" interface to the firewall, and the other being the "Internal" interface.

But where does my switch go, since I have 5 machines (or X number of machines). Where is the switch connected, to the internal interface on the VHost? What default gateway do my clients use etc? How would the routing work if these two interfaces weren't bridged since they are virtual networks anyway.

I'm a little confused! Any advice is much appreciated!


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up vote 3 down vote accepted

In this case, you need 2 Virtual switches: one for the external network, and one for the internal. You could do it with a vlan, but that has an added securirty concern that is easily solved with 2 virtual switches, so that is my recommendation.

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If you leave a downvote, it's considered good etiquette to leave a comment why. – longneck Sep 29 '12 at 21:34
Apologies Longneck, I didn't actually mean to down-vote it! Sorry again. – PnP Sep 30 '12 at 15:21

I would probably skip the Zyxel router or if it's a router/modem, leave it in bridge mode and use it strictly as a modem.

I'd then dedicate an interface on my virtual host as my "WAN" interface, assign that and another virtual interface/vSwitch as the "LAN" interface to my UTM virtual machine, just as you would on any VM you wanted on your physical LAN. You can also trunk VLANs if you have VLAN capable switches, but in the simplest scenario you wouldn't need to.

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How would I configure the default gateways, I've been struggling to get this working. Thanks! – PnP Sep 30 '12 at 15:05
First of all, do you have a working VM that you can ping on your LAN (assuming you have a flat LAN network)? – gravyface Sep 30 '12 at 17:47
Any chance we could take this to chat? – PnP Sep 30 '12 at 18:40

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