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I'm having a bit of a problem allowing traffic between two of my subnets. Here's the structure I've built.

The X0 interface has our windows server on it and it handles DHCP/DNS, etc. X1 has the WAN connection. The Sonicwall is handling DHCP on X2. The X3 interface is connected to a different vlan on the 48 port switch. The Sonicwall is handling DHCP on this network as well.

So here's what i want to do. The network on X2 is for our guest wireless; i don't want it to be able to access any of the other networks, just the internet, so i that all blocked in the firewall. No issues there. The X3 network is going to be for programmable controllers, and needs to be able to access the X0 network where our computers are. This is where my problem is. I'm not able to get between the and the on interfaces X0 and X3 respectively. I have these rules set up in the firewall. The Lan Primary Subnet is the on X0. So if i'm not mistaken, this will allow traffic between the two through the firewall. Now this is where I'm a little confused. Do i need to use NAT to get the traffic from X0 to go to X3 (and vice versa), or a static route, or both? Currently i have both, though i doubt they're done correctly (also in screenshot). I've tried to ping between the two without luck. Any advice, or if you see what's wrong with my setup, is much appreciated. If you need some more information, let me know. Thanks all!

EDIT: So i found that i don't neither either NAT or a static route, that the setting in the firewall is enough. I can now ping from the network, however i can't access the server on the network. When i try to access i get "An error occured while reconnecting to Z: to server Microsoft Windows Network: The local device name is already in use. This connection has not been restored. What am i missing?

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Taking an educated guess, based on the fact that you have two different subnets on one switch, you have Vlans implemented? You might be missing InterVlan routing then. – Davidw May 24 '14 at 3:35
@Davidw Yes, i do have a vlan implemented. I'm not sure if interVlan routing is enabled or configured (though i highly doubt it is), but i wouldn't think I'd need that anyway since both vlan's are on different interfaces on the sonicwall? It should act as if they are two physically different switches, which is why i'm confused as to why i would need interVlan routing. – Chris1499 May 27 '14 at 21:53
Yes, you do need to have InterVLAN routing configured in order for two different VLAN's to communicate. Even though they are physically on two different ports of a switch, they are virtually on two different subnets, and traffic on different subnets needs to go through a router (or layer 3 switch) in order to communicate. – Davidw May 28 '14 at 0:44
I figured out that the error i was getting is a firewall issue on the server, and that i have it configured correctly. @Davidw The sonicwall is acting as the router in this case. Thank you for your help! – Chris1499 May 29 '14 at 20:55

All that was required is a rule in the firewall to allow traffic between the subnets. The Sonicwall will route traffic between subnets by default, if allowed by the firewall.

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