How long does it take on average for DNS to update?
 

anyone know?

6-8 weeks.

last week took me 28 hours once and 22 hours the other time

24-72 hours globaly, but uhh, if you control dns it make take a few hours. all depends on when your isp updates with the root servers

12-48 hours .. guess it depends on where you are surfing from and which dns server your isp is using...

it takes 24-48 hours but if your host forgets to add your domain to their dns then it might never happen :|

starts at 24 hours and usually finishes within 72 these days.

no loger then 48 hours for me ever

average 24 to 36...diff each time for me

There are two major factors in DNS propagation. The first is your registrar, the second is the popularity of your domain.

Registrars play a factor in terms of when they make their updates live. Until your registrar updates its database to reflect your new nameservers, you're fucked. Network Solutions can take 24 hours plus for the new nameservers to show in their database. With DomainMonger, if you change your nameservers, the updates are live (to new queries) within seconds.

Popularity plays a factor in terms of caching of your IP at various nameservers around the net. If your domain is wildly popular and people are accessing it from all over the world, all the time, your old IP will be cached at various nameservers. DNS caches typically expire after a day or so, but the TTL varies per domain.

If you know in advance that you're going to be moving your DNS, and you run your own nameserver, set the TTL for your zone down to 1H a couple of days before the migration. As soon as you've migrated, set the TTL back to 1D. You'll see some increased DNS traffic during the migration, but it's worth it to have your updates propagate (and caches expire) more quickly.

One way to tell when your new IP is making the rounds is to resolve your domain via a couple of popular free nameservers:

nslookup yourdomain.com 4.2.2.2
nslookup yourdomain.com cache01.ns.uu.net

When your new IP shows up there, you're pretty much golden.

ohhh my goly gosh that was a good explination

3 years