help - multiple webhosts

[scorpion]

One of my webhosts is quite unreliable, is there a way to setup your domain names and sites such that you can use two separate web hosting companies? That is, is it possible to set the primary DNS to one web host co. and the 2nd, 3rd, or 4th DNS entries to a second web host co? Does this mean if the first company is not resolving your sites, it will automatically try it from the second web hosting co.? Are there other solutions to maintain 100% uptime?

[DaveAtIFG]

[webmasterworld.com...]
[webmasterworld.com...]
[searchengineworld.com...]

[scorpion]

Thank you,

Can someone explain what backup/redundancy systems one's webhost should have in order to provide 99.99% uptime, or something close to it?

For example, is it technologically possible that say one server is down to switch to a mirror site on the same host?

[Slade]

There isn't an all-in-one solution that I've ever seen advertised.

Such a solution would need to include:
multiple datacenters (or at least multiple independant backbones)
DNS servers on different boxes
multiple webservers responding to yourdomain's traffic
multiple system "i'm alive" checks with dynamic reroutability

Micro$oft has a decent setup in their datacenter, using a "Single-IP" solution. [microsoft.com...] There is an article there that discusses their setup.

[WibbleWobble]

to provide 99.99% uptime

Unfortunately, conventionally uptime doesn't mean online, if the connection goes down, it still can be attributed a percentage of uptime. Scandalous, really.

[scorpion]

it would be nice if web host companies had a mechanism to at least put a message on down sites when they do upgrades so it doesn't look like the site is fly-by-night, gone alltogether