There are other elaborate solutions to accomplish this, however all of them would require a competent IT/Network Person to manage the network. If we were the ISP, we would look at such a case an an opportunity, and become the managed service provider, for a fee (typically a premium), and provide the service. As service providers, we all complain about the end-customer being a pain, but we often forget that it the the PITA end-customers that give us the ability to earn our daily bread!.... I think too many of us are overworked and providing highly under-paid services for peanuts, where we often overlook at opportunities to get premium value as a PITA, and not worth it... :) Just my personal two cents,..... Faisal Imtiaz Snappy Internet & Telecom ----- Original Message -----
From: "Eric A Louie" <elouie@yahoo.com> To: "Randy Carpenter" <rcarpen@network1.net> Cc: "NANOG" <nanog@nanog.org> Sent: Monday, March 3, 2014 11:49:21 PM Subject: Re: ISP inbound failover without BGP
Honestly? Because the end-customers are not technically competent enough to run dual-homed BGP, and we don't want to be their managed service providers on the IT side. And announcing the AT&T space is fine until something goes wrong, and I have to troubleshoot the problem (Customer - "How come AT&T is down, and we're not getting inbound traffic to our servers?", and I discover L3 or CenturyLink isn't accepting my advertisement for some weird reason, but they won't fess up to it for a few frustrating hours)
________________________________ From: Randy Carpenter <rcarpen@network1.net> To: Eric A Louie <elouie@yahoo.com> Cc: NANOG <nanog@nanog.org> Sent: Monday, March 3, 2014 7:20 PM Subject: Re: ISP inbound failover without BGP
Is there some technical reason that BGP is not an option? You could allow them to announce their AT&T space via you as a secondary.
-Randy
----- Original Message -----
This may sound like dumb question, but... I'm used to asking those.
Here's the scenario
Another ISP, say AT&T, is the primary ISP for a customer.
Customer has publicly accessible servers in their office, using the AT&T address space.
I am the customer's secondary ISP.
Now, if AT&T link fails, I can provide the customer outbound Internet access fairly easily. So they can surf and get to the Internet.
What about the publicly accessible servers that have AT&T addresses, though?
One thought I had was having them use Dynamic DNS service.
Are there any other solutions, short of using BGP multihoming and having them try to get their own ASN and IPv4 /24 block?
It looks like a few router manufacturers have devices that might work, but it looks like a short DNS TTL (or Dynamic DNS) needs to be set so when the primary ISP fails, the secondary ISP address is advertised.