WAN Interface problem

[irfanink]

I have new device and when i am configure wan interface and give my ISP is its give me error that this ip is already used by other device ( which is my modem ip ) . so please guide me what should i do . i have only one IP from ISP.

[rosario_thobias]

Hi, Your ISP should give u what the wan public ip is, then the gateway ip of ur public ip, dns if u want etc. If you are not sure what's going on, I would suggest that you use your laptop and then set the static ip of ur laptop as the public ip, get the mask, and then set the gateway as the ip of ur modem ip. Typically ur modem would use the gateway ip. Now see if laptop can ping out. Then try the same on the firewall. The wan int of firewall would be ur public up. Then you need a route saying for eg: 0.0.0.0 0.0.0.0 <gateway ip as per isp modem>. This route will send all traffic to Internet.

[irfanink]

my public ip is 182.180 50.174 and my private ip is 192.168.10.1 which is my default gateway 

[rosario_thobias]

Only one of them is a public ip. It could be ur public ip or the gateway for ur public ip.

So if your connection is a simple lan to wan connection, that is, if you don't do VPN then your ISP should give two public ip's stating here is your public ip and this is the default gateway for ur public ip.

Is there a workstation where internet works? Is so, try googling what is ur public ip.

Then do a tracert to 8.8.8.8 maybe and let me know.

If your wan interface of the firewall is directly connected to the modem then,

WAN interface of firewall 182.180 50.174<------->LAN interface of modem and typically that should be something like 182.180 50.173 for eg.

i.e Your WAN ip of firewall and the modem should have ip in same subnets right. That's why I told u that ur isp should give 2 public ip.

[irfanink]

this is my WAN interface now i try to configure WAN interface and LAN Interface , and i want to give 192.168.10.50 ip to LAN by which i can access my fortigate device  and i don't need dhcp server of fortigate because i have already DHCP in my modem . Now please guide me what shoud i do  which i will give in wan and Lan ... and and i make a policy to allow internet and if any other policy or routing is required the please also share ??

[rwpatterson]

irfanink wrote:

this is my WAN interface now i try to configure WAN interface and LAN Interface , and i want to give 192.168.10.50 ip to LAN by which i can access my fortigate device  and i don't need dhcp server of fortigate because i have already DHCP in my modem . Now please guide me what shoud i do  which i will give in wan and Lan ... and and i make a policy to allow internet and if any other policy or routing is required the please also share ??

If the Fortigate is between your modem and your LAN, hosting the DHCP server on the modem will not work without a DHCP helper on the Fortigate. From what you have written it sounds like you are missing the basic networking knowledge to get all this working. I'm not trying to be a d!ck, but if you don't have the skeleton of networking down, then it is as if you are trying to build a castle on a sand dune. The foundation needs to be solid to get a good solid network built. The ISP's modem has the public IP address and is handing off (routing) a private range to the inside. Your Fortigate then would ride that INSIDE (private) subnet and hand off another private IP subnet to the Fortigate's LAN (internal). DHCP is not a routable protocol (UDP) so it needs a helper in the Fortigate so your internal clients could get DHCP from the ISP's modem. In my opinion, if the ISP's modem is Ethernet connected to the ISP, I would chuck it and put the Fortigate on the edge. This will save you tons of headaches in the future.

[ede_pfau]

Well versed, Bob, and so true.

[irfanink]

Can i get your skype so i will discuss with you i am really stuck for last 4 days  

[rwpatterson]

Make sure the edge device your ISP gave you is in bridge mode. This way it passes the public IP address through to your Fortigate. Otherwise, it will route the public IP and give you a private IP address off of one of it's internal ports.