[169557] in North American Network Operators' Group
Re: ISP inbound failover without BGP
daemon@ATHENA.MIT.EDU (Randy Carpenter)
Mon Mar 3 22:21:10 2014
Date: Mon, 3 Mar 2014 22:20:42 -0500 (EST)
From: Randy Carpenter <rcarpen@network1.net>
To: Eric A Louie <elouie@yahoo.com>
In-Reply-To: <1393895467.63537.YahooMailNeo@web181605.mail.ne1.yahoo.com>
Cc: NANOG <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Is there some technical reason that BGP is not an option? You could allow t=
hem 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.
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> Here's the scenario
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> Another ISP, say AT&T, is the primary ISP for a customer.
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> Customer has publicly accessible servers in their office, using the AT&T
> address space.
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> I am the customer's secondary ISP.
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> Now, if AT&T link fails, I can provide the customer outbound Internet acc=
ess
> fairly easily.=C2=A0 So they can surf and get to the Internet.
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> What about the publicly accessible servers that have AT&T addresses, thou=
gh?
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> One thought I had was having them use Dynamic DNS service.
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> Are there any other solutions, short of using BGP multihoming and having =
them
> try to get their own ASN and IPv4 /24 block?
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> It looks like a few router manufacturers have devices that might work, bu=
t 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.
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