Solved: Router to ISP

Ivan Adji - Krstev · ‎07-07-2016

Hi all,

We have Router 4331 and I need to connect to the ISP. In the background we have a switch that will be connected with other switches with 3-4 Racks. So im gonna do a NAT on the Router but than i have have to go out from that Router to the ISP Router. And how should i configure that connection, between My Router and ISP Router. Using default gateway for the NAT Subnets to go out there via ISP or just simple static routes ?

Or there is a specific connection that have to be with My Router and ISP Router ...

Kind regards

Ivan

Francesco Molino · ‎07-07-2016

Hi

On your router you will have a port acting as outside interface.

This port will be configured with static ip if your isp provided one or by dhcp.

To forward traffic out to your isp you will need usually a static route (sometimes isps are doing dynamic routing like bgp or ospf).

Your static route would be:

Ip route 0.0.0.0 0.0.0.0 x.x.x.x ==> your isp router address as next hop

OR

Ip route 0.0.0.0 0.0.0.0 dhcp ==> if you're in dhcp with your isp, he will send the default route next-hop information by dhcp.

If your are using pppoe, instead of dhcp, the next bgp will be the dialer interface.

For sure this wan interface has ip nat outside configured and on your lan interface you'll have ip nat inside configured in order to allow all internal hosts to get access to Internet.

Hope this is clear.

Thanks

PS: Please don't forget to rate and mark as correct answer if this solved your issue

Thanks
Francesco
PS: Please don't forget to rate and select as validated answer if this answered your question

View solution in original post

Francesco Molino · ‎07-07-2016

Hi

On your router you will have a port acting as outside interface.

This port will be configured with static ip if your isp provided one or by dhcp.

To forward traffic out to your isp you will need usually a static route (sometimes isps are doing dynamic routing like bgp or ospf).

Your static route would be:

Ip route 0.0.0.0 0.0.0.0 x.x.x.x ==> your isp router address as next hop

OR

Ip route 0.0.0.0 0.0.0.0 dhcp ==> if you're in dhcp with your isp, he will send the default route next-hop information by dhcp.

If your are using pppoe, instead of dhcp, the next bgp will be the dialer interface.

For sure this wan interface has ip nat outside configured and on your lan interface you'll have ip nat inside configured in order to allow all internal hosts to get access to Internet.

Hope this is clear.

Thanks

PS: Please don't forget to rate and mark as correct answer if this solved your issue

Thanks
Francesco
PS: Please don't forget to rate and select as validated answer if this answered your question

Ivan Adji - Krstev · ‎07-08-2016

Hi and thanks for the reply.

Ye this is the correct answer i just wasn't sure if that is all it need to connect to ISP ? If all it need a Routing that is easy. But the part if it need PPPOE i don't get it. It should have again a route configuration where the next hop will be bgp interface on the ISP site or ?

Any way i think we wont have pppoe so i think this is what i need.

Thanks

Ivan

Francesco Molino · ‎07-08-2016

Ok. You're welcome.

If you need help let me know

Thanks
Francesco
PS: Please don't forget to rate and select as validated answer if this answered your question