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I need to send 3 vmWare ESXi servers (hosts) to thee locations around the world. Each host will have 3-5 guest VMs performing various tasks. Each host will live behind a firewall configured with a branch office VPN tunnel back to our HQ. Each remote office will have it's own private network configured so that it does not match any other IP/Subnet of other remote offices. Pretty basic.

I want to simulate the WAN environment so that I can setup all the guest VMs here before sending them off to their future homes. Specifically, I want to test communication from server-to-server and make sure they can talk while on different subnets. I know that the firewall/VPN setup will allow this but I'd like to test it before it's thousands of miles away.

HQ Network 172.16.0.0/16

Remote Office Network 1 192.168.1.0/24

Remote Office Network 2 192.168.2.0/24

Remote Office Network 3 192.168.3.0/24

Remote Office Network 4 192.168.4.0/24

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This honestly sounds like it will be more trouble than it's worth. Even duplicating your WAN structure and rules in a virtual enivornment won't effectively simulate the differences between LAN and WAN links. –  HopelessN00b Aug 6 '12 at 14:58
    
@HopelessN00b I agree as for WAN performance (see my full answer), but I can understand his desire to test basic connectivity of the Esx/VMWare environments before shipping. If you can't get at the VMWare console because of an incorrect default gateway setting somewhere... You may end up trying to talk someone non-technical through reconfiguring the Esx environment over the phone. (The stuff nightmares are made of...) –  Tonny Aug 6 '12 at 15:10

2 Answers 2

That is not so complicated, but you will need a router (or switch with router capability) to do so, just for basic connectivity tests.
Just setup 5 LAN's on the router, one for each subnet and configure the router on each subnet to behave as if it is the WAN/VPN router for the site.
Then hook everything up.
Of course you will have only 1 router-hop where in the real setup there will be many, but for the connection logic of the VM's that won't make any difference. You can test all your VM's and/or applications in this way.

You can't really test the VPN's themselves, unless you have a bunch of VPN capable routers at your disposal. Even then your setup will look nothing like the real thing. I wouldn't bother with that.

Simulating slow/bad latency on a WAN link can be done through a Linux box as mxrx already mentioned in his answer.
This will also act as the router so you may want to setup a VLAN capable switch to provide the 5 subnets as VLAN's + 1 additional trunk-port onto which you configure the router-PC as a router on a stick. No expensive hardware-router required.

If you are not interested in doing simulated WAN performance tests you can take this approach too, using pfSense as a software router.

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A WAN link is going to represent reduced bandwidth, some (hopefully minimal) amount of packet loss and - most importantly - higher latency. You can set up a Linux box with IP forwarding enabled and four interfaces, one for each of the subnets defined. Look here for some discussion of setting parameters to vary latency, bandwidth and packet loss on the circuit. It's hard to guess how bad your latency will be without understanding specifically where the circuits run and the type/speed of the media, but you can always try some pretty rough cases (say 300ms if on the same continent and 600-900 if longer) to see how it plays out.

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Unfortunately and perhaps more embarrassing is that my question was geared more towards the networking portion of this problem. I do appreciate your guidance on how to simulate real world network/Internet speeds though. I was going to add that to the test later. First, I need to figure out how to setup the WAN simulation within my network to make the different subnets talk. Perhaps my question should have been worded differently- I apologize. –  Jason Aug 6 '12 at 15:01

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