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Contributor III
April 20, 2009
Question

fortigate behind a dsl modem for IPSec VPN

  • April 20, 2009
  • 4 replies
  • 4123 views
in the last post i asked for a help and i got it. but now i have faced another problem. The internet connection is dsl. So i remove the dsl modem (fritzbox) and connect fortigate (50b) directly with the internet. Because I got the information from the vpn administration guide that at least the firewall should have one static public IP address. but when I choose the wan1 port for PPPoE and give username and password from the isp provider. it can not syncronized to get that real ip address from the provider. so is there any possibility that the dsl modem will be connected with the internet and the fortigate will be behind that? if it' s then what TCP and UDP port should be open in the dsl modem to connect with the fortigate. i do apologize for the lack of my knowledge.

    4 replies

    red_adair
    New Member
    April 21, 2009
    I assume you just used your Fritzbox before ? Where the ADSL-Modem itself is located in the Box. FortiGate does not have an integrated DSL Modem, hence you need a separate Box for this. You can change the Fritzbox to be " ADSL Modem only" (no Router or whatsoever). FortiGate than is hooked up to Fritzbox with a crossover cable and will do PPPoE; means FGT will get the public IP from your ISP. ---------------[Splitter]------------[FritzBox]-----*crossover*------(FortiGate)---------
    doshbass
    New Member
    April 21, 2009
    hi Winterday, IPSEC is an IP protocol not a TCP or UDP port. Your DSL modem should have the ability to forward all traffic directly to your Fortigate. Your WAN1 connection would then be on a private subnet that is different from your internal subnet. e.g. if your internal network is 192.168.1.0/24 make your wan1 192.168.2.1/24 and your DSL router internel network 192.168.2.2/24. Tell teh DSL router to forward all traffic to 192.168.2.1.
    doshbass
    New Member
    April 21, 2009
    I am about 1 min behind red coming with alternatives :-) Both solutions should work provided your ISP supports PPPoE
    Contributor III
    April 21, 2009
    Yes doshbass ur right. i just changed the fritzbox adsl router modem into dsl and i will forward the update. thanks ...... for perfect assist!
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