I heard about this in other posts (couldn't find them anymore). And it looked like an fast (& easy?) way to redirect surfers from on host to another.
But I don't realy understand this stuff. So I wanted to ask ya'll advice w/ an example.
Suppose you have 2 hosts:
-A= a very cheap or a free host (cheap bandwith, but unreliable sometimes)
and
-B= a more expensive or a paid host. (expensive bandwith but reliable)
Suppose you have exactly the same website hosted on both of them.
When surfers go to your site, they go to the one hosted on A.
BUT one day the server of host A goes down.
If you host your own DNS(?), you can forward you surfers almost instantly to your mirror-site on host B. This is much faster than changing the nameserver.

I'm not quite familiar w/ all this.
1. Is all what I said correct? (What wasn't?)
2. How do I host my own DNS?
3. How much does this cost?
4. What are the (dis)advantages of it?
5. What do you think about this? And what are your experiences w/ this?

Yes you could mirror the sites. Their are several "managed dns" companies that can do this for you. What you would do is move your domain to their name servers then you become "host neutral." When one of your web hosts bites the dust you log onto the managed dns system and change the ip (or web forwarding) to the second host. Ultradns.com can do this switch in under 5 mins. You just need some alert software telling you that host #1 is down (because I doubt they are going to tell you)

Thanks for replying so fast.
The 'smoke' has cleard now ;)
Ultradns is a paid service, are there any free ones?

mydomain.com does it.