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New Member

configure dns failover

How do I configure DNS Failover?

- I have domain hosted through Network Solutions

             - Have noticed that I can configure 4 DNS Servers through Network Solutions

- I use two ISP's :: Verizon and Comcast ..

Need basic info from ground up..

- Do I logon to Network Solutions and configure the DNS on the site to begin with?

- Do I use two separate (different) IP's :: Comcast and Verizon?

- I have read that Cisco ASA 5505's can assist with the Failover, is this correct?


Further info would be greatly appreciated



Everyone's tags (1)

If netsol is hosting your

If netsol is hosting your website, DNS failover is not your responsibility. They will take care of that.

Not sure how ASA can help.


New Member

with ASA 5505 you can

with ASA 5505 you can configure the ISP failover. For the DNS, the host are configured on the client in your LAN enviroment. The DNS server can be in network solutions.

New Member

The ASA can do ISP failover

The ASA can do ISP failover and it can DNS for internal clients, but it is not an authoritative DNS server, so it cannot redirect from using a static IP on one of the ISPs link to using a static IP on the other ISP link if one goes down. For that you need something like this:


New Member

Would you not just specify a

Would you not just specify a Primary DNS server and a Secondary DNS server?  That way if for whatever reason the Primary DNS server didn't respond the client would use the Secondary instead.  If you have the ability to specify 4 use either the Pri & Sec supplied by your 2 ISP's or the 2 Pri and say Googles DNS ( &

New Member

No, I'm pretty sure

No, I'm pretty sure EdFord2000 is talking about authoritative DNS where he can switch DNS for from a static IP on his Verizon link to a static IP on his Comcast link when one or the other goes down.


But you would be correct for recursive DNS, e.g. the resolver(s) your personal computer uses to resolve DNS when surfing the Internet. In that case, just load it up and your machine will cycle through them if one happens to be down.

New Member

Ah I see, I was looking at it

Ah I see, I was looking at it from the point of view of DNS outbound, not DNS inbound.


Thanks for clarifying. :)