how do i achieve High availabiltiy networking?

szboardstretcher · 06-03-2011, 01:58 PM

How do the big companies, like Amazon, Google and the like, handle High network Availability?

For example.

If I go to google.com, it will take me to 76.23.10.20.

But if that is down, or extremely busy, it will send me to a different IP. Even if the address is cached, it still seems to force a change.

How do I achieve this? Is there a High Availability, Resource Monitoring, Round Robin DNS changing service or something?

acid_kewpie · 06-03-2011, 02:35 PM

They use things like F5 GTM / LTM for global DNS balancing. Terms like HA networking mean all sorts of things though, no one solution is the obvious choice. Indeed what you're asking about isn't actually networking at all, really is it? I was expecting queries more about multiple internet pipes and routing protocol failover.

You wouldn't be round robin-ing though... that's not very HA is it? That just means that when one of two systems is dead every second request will fail. There are much more intelligent ways to do things like that.