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Sonicwall TZ105 WAN Interface gets private ip address?

I have a new Sonicwall TZ-105 firewall appliance which will be on a small office network and will participate in a site-site VPN.  The WAN interface is set to acquire an address via DHCP from the attached cable modem.   When I look at the configuration of the firewall, the LAN port has an IP of  The WAN interface has an ip address of and I can't figure out where that is coming from.  If I go to whatismyipaddress.com it gives me a correct public ip address and everything appears to function normally even with a private IP on the WAN interface.  Because the WAN port has a private IP, I can't manage the device over the Internet, do any port forwarding nor connect it to the VPN.  Why is the sonicwall giving the WAN interface a private IP address?  Does it need to be in some other mode?  I believe I chose the default setting, which was WAN/LAN switch.
Steve Bantz
Steve Bantz
1 Solution
Henk van AchterbergSr. Technical ConsultantCommented:
Your cable modem is probably a router which is also performing NAT and thus giving you a private IP.
Steve BantzIT ManagerAuthor Commented:
Good call.  The model of cable modem provided was a combination modem/router/wireless access point.  The cable company had to put it in bridge mode so it would pass the public IP directly to the WAN interface.  I was unaware that the cable modem was anything but a run of the mill device.
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