How to publish web server on multiple ISP but with single IP

[Sujeet Gond]

My web site map with one of the ISP1 public 100.1.1.1 now I'm planing to take 2nd ISP2 so ISP1 go down my website work with ISP2.
how can i achieved this can any one suggest problem is both ISP is different and they are not ready to publish each other public IP to their own network
so their is any way to deal with this condition .
If ISP 1 goes down .how to use same ip address for web-server that is 100.1.1.1 with ISP2 .Outside users should be able to access 100.1.1.1 via isp2 in case isp1 goes down.

[willwetherman · Accepted solution]

Hi,

I had a similar challenge to this. If the same IP addresses cannot be advertised via both ISPs then one option is to use DNS with a low TTL. In the event that ISP 1 fails, you can update your DNS record to point to the ISP 2 IP address. This can also be automated if you use a failover DNS service that will proactively monitor you web server via ISP 1, and if that fails, it will automatically change the DNS records for you. The only issue with using DNS for this is caching as some providers ignore the low TTL which can cause a delay for the records to be updated on the end users device.

This worked ok for my situation as the customer didn't need immediate failover and it removed the need to ask users to use a different IP/hostname on their apps to connect to a central web service.

I hope that this helps

[Sujeet Gond]

Thanks for your solution.

My website is register with godaddy so if ISP1 link down i have to tell godaddy to point the DNS to ISP2