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Community Member

WAN Connectivity

Hello Guys.


I have attached my network Setup. We have recenlty bought other ISP line in order to provide failover/load balnce traffic to my inside users and servers.Currenlty ISP1 is acting as a primary and serving all traffic.


ISP2 is a NBN line where i am getting a static IP address from ISP dhcp server. I am able to get an IP Address and interface status is up. This eedge router has got NAT,ACL and BGP Configuration.


Now, in order to test it i have geenrated couple of ping packets to public DNS server using ISP2 interface as a source IP and haven't got any reply. Initailly i was thinking it could be a line issue then i connect my laptop to ISP line and everything was working as per expectation.


i am wondering what could block this communication in the router when i am generating traffic from router itself(mentioning source as a router ISP 2 interface).

I thought it might be routing table which probably redirrecting traffic towards ISP1 as we have got a default route towards them. Later on i Put a static route 

IP route <isp 2 interface name> and still i can't reach to the server.


can anybody advise me what could be root cause?

also i want to know does NAT coming into the pitcure for router generated traffic also? as per my understadning  natting would be for through traffic not for to.


Look forward to have some valuable inputs.




Hello.For test purposes you


For test purposes you need to use not interface in your static route, but the exact next-hop per DHCP.

If you run BGP with ISP2, then why (and how) do you have DHCP on the link?!

Community Member

 i am not running bgp over

 i am not running bgp over second isp. my router is getting IP address from ISP as a DHCP Client.


I did put static route to overwrite current default rule. Also, i am wondering how does it matter if i put a ISP2 interface in static route instead of next hope ip address.

Hello.If you don't advertise


If you don't advertise your prefix via BGP to second ISP, then you need a configuration for dual-ISP NAT.

If you configure static route via Ethernet interface without next-hop (which is not a best practice), then your router would have to query interface with ARP requests for all destinations it tries to send packets to! And this could work, if ISP had proxy-arp enabled.

Community Member

yup you are right, we have

yup you are right, we have multi nat setup in order to use both ISP. 



Community Member

Can you post your Router

Can you post your Router configuration for review?

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