Redundant Data Center Architectures

Wed Oct 28 20:57:02 UTC 2009

Also, commercial solutions from F5 (their GTM product and their old 3-DNS
product).

Using CDN's is also a way of handling this, but you need to be prepared for
all your traffic to come from their source-ip's or do creative things with
x-forwarded-for etc.

Making an active/active datacenter design work (or preferably one with
enough sites such that more than one can be down without seriously impacted
service) is a serious challenge.  Lots of people will tell you (and sell you
solutions for) parts of the puzzle.  My experience has been that the best
case is when the architecture of the application/infrastructure have been
designed with these challenges in mind from the get-go.  I have seen that
done on the network and server side, but never on the software side- that
has always required significant effort when the time came.

The "drop in" solutions for this (active/active database replication,
middleware solutions, proxies) are always expensive in one way or another
and frequently have major deployment challenges.

The network side of this can frequently be the easiest to resolve, in my
experience.  If you are serving up content that does not require
synchronized data on the backend, then that will make your life much easier,
and GSLB, a CDN or similar may help a great deal.

--D

On Wed, Oct 28, 2009 at 10:57 AM, Roland Dobbins <rdobbins at arbor.net> wrote:

>
> On Oct 29, 2009, at 12:42 AM, Ray Sanders wrote:
>
>  Could you elaborate on "GSLB"  (Global Load Balancing?) ?
>>
>
> Architectural choices, implementation scenarios, DNS tricks to ensure
> optimal cleaving to and availability of distributed nodes within a given
> tier:
>
> <http://www.backhand.org/mod_backhand/>
>
> <http://www.backhand.org/wackamole/>
>
> <http://www.spread.org/>
>
> <http://www.dsn.jhu.edu/research/group/secure_spread/>
>
> <http://wiki.blitzed.org/DNS_balancing>
>
> <http://www.cisco.com/en/US/products/hw/contnetw/ps4162/>
>
>
> -----------------------------------------------------------------------
> Roland Dobbins <rdobbins at arbor.net> // <http://www.arbornetworks.com>
>
> Sorry, sometimes I mistake your existential crises for technical
> insights.
>
>                        -- xkcd #625
>
>
>

-- 
--  Darren Bolding                  --
--  darren at bolding.org           --