Hello people!
I recently setup an opnsense system (using an old Dell Optiplex 755 with HP NC364T Quadport NIC).
Here's the Setup:
ISP Router (Assigns DHCP 192.168.x.x to PF Sense WAN)
|
|
|-------DELL Optiplex (runs Ubuntu Server 17.04 with 4GB RAM, VirtualBox headless)
      |
      |
      |-------> VM1 - Opnsense (Opnsense 17.x, 1GB Memory)
      |      |
      |      |
      |      |---> Adapter 1 uses NIC#1 (Opnsense WAN) - Bridged Adapter (Intel PRO/1000 T Server 82543GC)
      |      |---> Adapter 2 uses NIC#2 (Opnsense LAN) - Bridged Adapter (Intel PRO/1000 T Server 82543GC)
      |         |
      |         |
      |         |---> Wifi Access Point 1
      |         |---> Wifi Access Point 2
      |
      |
      |-------> VM2 - Apps (Ubunt Server 17.04, 1.5GB Memory and has virtualbox guest addons installed)
            |
            |
            |---> Adapter 2 uses NIC#2 (Opnsense LAN) - Bridged Adapter (Intel PRO/1000 T Server 82543GC)
The problem that I'm facing is that (although the network adapters are all Gigabit) my internet speeds seem to be limited on VM2.
I get between 40-50% of my internet bandwidth on VM2 but if I change the network adapter on VM2 to NAT (skipping opnsense and hooking onto the Dell Optiplex directly), I get 100% of my internet bandwidth (I tested the bandwidth by using wget to download a big iso file).
So the problem seems to be with some sort of throttling with the data going through opnsense.
Note: I don't have traffic shaping enabled on opnsense.
			
			
			
				UPDATE:
I upgraded to the latest opnsense which is based off FreeBSD 11.1 but the issue, remains.
The solution for my problem was to disable nested paging under VM -> System -> Acceleration, after which the I could use 100% of my bandwidth.
 
(https://i.imgur.com/Ecs6WA4.png)
			
			
			
				Thanks for reporting back!
Sure someone else will find this post with similar issues and may get it fixed too.