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U-Verse, Static IP block, and Sonicwall


U-Verse, Static IP block, and Sonicwall

I have a Sonicwall firewall sitting behind my AT&T RG (3800) in DMZ Plus mode.  the RG has a public IP address of 99.x.x.x.x and 192.168.0.x as provate. The public IP was passed via DHCP to the SonicWall's WAN port. The LAN and WLAN are on subnets 192.168.1.x and 192.168.2.x


I ordered a static IP block in order to configure my SonicWall's SSLVPN. AT&T gave me a x.x.x.192/8 that makes a block of x.x.x.192 through x.x.x.200. Based on this I configured x.x.x.199 under supplemental networks. (IP Address and subnet)


I set the new public IP given by AT&T (x.x.x.199) as the address for the WAN interface, and tried setting x.x.x.1 as gateway, and as DNS. This does not allow me to browse the internet at all. I can't access my SSLVPN either.


I then configured the WAN port as x.x.x.198 and gateway 99.x.x.1 and although it is not "technically" correct.. I can reach the internet.

However, this configuration also does not allow me to reach my SSLVPN.


I wonder.. how exactly should I configure it with the new static IP block, so I can acess internet and my SSLVPN?


I will appreciate any help you can provide.

Message 1 of 5
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Accepted by LowBoost
‎09-30-2015 1:39 AM

Re: U-Verse, Static IP block, and Sonicwall

First, you need to get your IP addressing correct. You have IP addresses X.X.X.192/8. This means you have:

X.X.X.192 - Not usable, network address
X.X.X.193 - Usable
X.X.X.194 - Usable
X.X.X.195 - Usable
X.X.X.196 - Usable
X.X.X.197 - Usable
X.X.X.198 - Assigned to RG
X.X.X.199 - Not usable, broadcast

On the RG, you need to go into the supplemental networks and assign the address as X.X.X.198, with a subnet mask of

Then go into your SonicWall, set the WAN port as X.X.X.197, subnet mask, default gateway of X.X.X.198.

This should get you running.
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Message 2 of 5

Re: U-Verse, Static IP block, and Sonicwall

Thanks… that certainly fixed my problem.

Message 3 of 5

Re: U-Verse, Static IP block, and Sonicwall

Is there any reason to use anything but 100-full on the Sonicwall WAN interface?

Message 4 of 5

Re: U-Verse, Static IP block, and Sonicwall

Normally, Ethernet ports should be left to auto-configure their speed and duplex unless you have good reason not to.

On the SonicWall, "Auto" should negotiate with the RG and come up as 100Mbps full duplex.
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