Benjamin Smith <lists@xxxxxxxxxxxxxxxxxx> wrote:
> I've been exploring high-uptime availability solutions for
> our own, database-driven ASP. We have two sites, much as
> original poster describes, and 5-minute DNS, but many
larger
> providers (EG: SBC, AOL) have DNS servers that seem to
ignore
> TTL.
Apparently many others here serve content to users on
networks other than those on AOL, SBC, etc... Or at least
their comments seem to repeat that. ;->
It's gotta be either that, or it's the reality that they keep
testing when their servers are using DNS that talk directly
to (or are the) authority for the domain.
I suspect the latter. ;->
> So, I've been at a quandary on this very same issue. We had
> a problem about 2 years ago where we had to switch to the
> failover in an emergency. From our end, we were "back up"
in
> < 3 hours, (far less than the 6 hours allowed by contract)
but
> it took over 48 hours for availability to approach 100%,
due to
> the aforementioned DNS issues. (I hate you, SBC!)
Which is why you need 1-to-1 NAT for near-immediate uptime.
Of course, that doesn't help you if the provider of those IPs
can't reach your 1-to-1 NAT equipment. That's why it's not a
true failover.
An ideal, although bandwidth using, solution is to keep your
router/1-to-1 NAT equipment at different locations. E.g.,
you have 4 sites -- 2 router/NAT, 2 servers. Only if and
when you lost 3 sites would you go down.
But that gets mighty expensive. Which brings us to the next
concept ...
> So, do you know of a "getting started" for how to get an
> autonomous system number and run BGP? My skills as a
network
> admin are a distant second to my primary skills...
In the US, start with the authority, ARIN --
http://www.arin.net/ They will give you the "do it yourself"
cost.
I suspect you're below that, so you need to talk to your
provider(s) about a solution. Unless you have just 1
provider (which means you're putting all your eggs in their
backbone basket), it's pretty tough to do without ARIN at
some point.
That's why it's typically better to rely on a partner who
already has their own AS, and ties into 3+ providers. Again,
this isn't something that you can do on your own, unless you
have a lot of dough.
Again, this is where the small-to-medium ASP finds
him/herself at the point where they either have to make a
major investment to go bigger, partner to go bigger (although
they will always be smaller than the partner), etc... It is
*NEVER* something you can do in software, and that's the
chronically dead wrong assumption.
--
Bryan J. Smith Professional, Technical Annoyance b.j.smith@xxxxxxxx http://thebs413.blogspot.com
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*** Speed doesn't kill, difference in speed does ***
