Unable To connect ISA2004 to an DSL router using PPPOE

Posted on 2007-07-24
Last Modified: 2008-11-17
I have an ISA2004 installed in a windows 2003 domain
iam currently using the dial-up interface to connect the ISA to the DSL modem and it works fine. I want to be able to use an dsl router to do the dialup thing so that i dont have to manualy press the dialup connection.
my internal netowrk address is no gateway
my external is no gateway
I have a adsl router and it's configured with the ip i have also set the DMZ to
network bindings are in the following order : internal then external

i connect the ISA external interface  to the dsl router ( in one of  the lan ports )
i connect the cable that is coming out of the ISP modem to the WAN port of the dsl modem  so that a PPPOE is estableshed .
The problem is it does not work , i try to ping and i also try to access the it also does not work. I also realized that when i unplug the internal cable , im able to ping the router but unable to access the web interface .
Can anyone explain how can i fix this problem as i have been trying for a while thanks.
please not that the router was tesed on another pc and it work fine , also no firewall is e
Question by:Dj_maj
    LVL 32

    Expert Comment

    Do you have remote administration enabled. It looks like you come into the router from the WAN side so router firewall may be blocking this, enable remote admin and use authentication on the port selected.

    Alternative open port 80 and allow selected IP only.

    Unless I misread your post that is ;o)


    Author Comment

    i tried what you said and it did not work , also the firewall is completly disabled as i said that the router was able to establish a connection when it's connected directly to the modem .
    LVL 32

    Accepted Solution


    I am trying to get my head around your topology

    Where is your DMZ? From your post it looks like on a port behind the Router (LAN Subnet 10.10...)
    The Router connects on a WAN port (public IP)
    The Router itsef has 192 subnet.

    As you go across multiple subnets, have you got NAT enabled, also shoudl your Router not be the gateway for your domain.

    Am I missing something?

    All the best

    Author Comment

    the DMZ is set to which is the internal isa interface. The broadband router has 2 cables connected to it , one from the external isa interface to one of the Router LAN ports The other cable is connected from the ISP modem to the the Router WAN port which is configured to PPPOE. The external isa interface was set to obtain auto ip but nothin happened , so i set a static iP which is . Hope this gives you a better view.

    Author Comment

    hi guys,
    i have installed isa2006 recently and the automatic dialup thing seems to work perfectly even after remote reboot unlike in 2004. so therefore i dont need an dsl router to do the dial up thing for me.
    LVL 32

    Expert Comment

    Great stuff, glad it worked out.

    All the best

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