[150548] in North American Network Operators' Group
Re: Reliable Cloud host ?
daemon@ATHENA.MIT.EDU (Jared Mauch)
Mon Feb 27 12:10:33 2012
From: Jared Mauch <jared@puck.nether.net>
In-Reply-To: <CAP-guGV++cqRfNs9aC0zxRB0rLP4LgCAOTA+55ehELQP3QiFUA@mail.gmail.com>
Date: Mon, 27 Feb 2012 12:09:21 -0500
To: William Herrin <bill@herrin.us>
Cc: Nanog <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Feb 27, 2012, at 10:28 AM, William Herrin wrote:
> On Mon, Feb 27, 2012 at 9:39 AM, Jared Mauch <jared@puck.nether.net> =
wrote:
>> Is the DNS service authoritative or recursive? If auth, you can
>> solve this a few ways, either by giving the DNS name people
>> point to multiple AAAA (and A) records pointing at a diverse
>> set of instances. DNS is designed to work around a host
>> being down. Same goes for MX and several other services.
>> While it may make the service slightly slower, it's certainly
>> not the end of the world.
>=20
> Hi Jared,
>=20
> How DNS is designed to work and how it actually works is not the same.
> Look up "DNS Pinning" for example. For most kinds of DR you need IP
> level failover where the IP address is rerouted to the available site.
If you want a system with 0 loss and 0 delay, start building your =
private network.
I'm never claimed your response would be perfect, but it will certainly =
work well enough to avoid major problems. Or you can pay someone to do =
it for you. I'm not sure what a DNS hosted solution costs, and I'm =
geeky and run my own DNS on beta/RC quality software as well ;).
What I do know is that my domain hasn't disappeared from the net =
wholesale as the name servers are "diverse-enough".
Is DNS performance important? Sure. Should everyone set their TTL to =
30? No. Reaching a high percentage of the internet doesn't require =
such a high SLA. Note, I didn't say reaching the top sites. While =
super-old, http://www.zooknic.com/Domains/counts.html says > 111m named =
sites in a few gTLDs. I'm sure there are better stats, but most of them =
don't need the same dns infrastructure that a google, bing, Facebook, =
etc require.
If your DNS fits on a VM in someone else's "cloud", you likely won't =
notice the difference. A few extra NS records will likely do the right =
thing and go unnoticed.
- Jared=
