How To Check If DNS is propagated ?

[Kamalkk]

Hi,

Whenever there is a DNS change, everyone says it takes about 24 to 72 hours for getting propagated fully around the globe. Is it true that the upper limit is 72 hours ?

In the middle of this transition periond, is there a way to check if my DNS has propagated fully ?

Looking forward for your answers.

Thanks
Kamalkk

[EarlyOut]

You'd have to check every DNS server in the world to be sure that the change "has propagated fully." Good luck with that.

[GatorMWalsh]

Typically it would be 48 hours on the end of that spectrum, not 72. As far as checking there really is not a way to check to see if it's propagated for everyone. There are sites like http://just-ping.com/ that you can view to see which IP it's pinging to but obviously they don't ping from every location in the world. That's the best that can be checked though unfortunately.

[GatorFPonce]

I'd recommend checking out sites such as http://IntoDNS.com as well, so that you know your DNS is configured properly, rather than just waiting 72 hours to see if it works. If DNS is configured properly, you could generally see a domain working in as short as 24 hours. It can be incredibly frustrating to realize that you've been down for three days waiting and have gotten no closer to resolving a problem.

[EarlyOut]

The problem is that something like OpenDNS may pick up changes within minutes, but other servers might not get updated for many long hours. There's really no way to tell.

[GatorEAnderson]

The site internetsupervision.com can ping a site from a bunch of locations around the world. It may give you a good idea of world-wide propagation.

It will also give you some idea of how long your page takes to load in different regions.

[aeons]

I can usually get domains to propagate (for myself) instantaneously by resetting the DNS cache in my PC.

In windows:
Start -> run -> type "cmd" (no quotes) -> type "ipconfig /flushdns" (no quotes)

close all browser windows, open a new session and try to access the site.


For your visitors, unless they know you moved/updated and have the knowledge for this, they won't see the same thing you are; unless they are a first-time visitor. They'll be loading your website through the DNS cache and still be seeing old data.

DNS cache updates every few hours to once a day, etc.
The ping/checker sites people suggested will function identically to your visitors, if you regularly use those tools, they'll be caching old DNS data, too.

[EarlyOut]

Originally Posted by aeons

I can usually get domains to propagate (for myself) instantaneously by resetting the DNS cache in my PC.

That will work only if the DNS server your PC is pointing to has, in fact, been updated. If the DNS server you're using hasn't gotten the propagation information yet, you can reset the cache on your PC all day, and not get the change.

[aeons]

Originally Posted by EarlyOut

That will work only if the DNS server your PC is pointing to has, in fact, been updated. If the DNS server you're using hasn't gotten the propagation information yet, you can reset the cache on your PC all day, and not get the change.

Very true. I suppose it also depends on registrar as well. I've been using this technique with Godaddy for about 6-7 years and haven't had it fail yet to-date.

[EarlyOut]

Originally Posted by aeons

Very true. I suppose it also depends on registrar as well. I've been using this technique with Godaddy for about 6-7 years and haven't had it fail yet to-date.

The registrar rarely makes any difference. It's the DNS server that your PC is using that matters.

[GatorAWatkins]

One way to check to see if a DNS change has made it to your computer would be to flush your DNS caching as mentioned earlier.

http://support.hostgator.com/article...vers/flush-dns

Then ping the domain:
1) Open a command prompt. Assuming you have Windows, click Start --> Run, then type "cmd" without the quotes into the run box, and press Enter.
(you may be able to bring it up with ctrl+r)
2) Type the following into the command prompt: ping YOURDOMAIN.COM
3) Press Enter

You should see, among other things lines something like this:

Reply from IPADDRESS: bytes=32 time=6ms TTL=56
Reply from IPADDRESS: bytes=32 time=6ms TTL=56
Reply from IPADDRESS: bytes=32 time=6ms TTL=56
Reply from IPADDRESS: bytes=32 time=9ms TTL=56

When you see your IP above where "IPADDRESS" is you will know it's resolved to you, but depending on how your local nameservers update it may bounce a little back and forth. You can find your IP address by logging into cPanel and viewing the stats on the left hand side. Keep in mind that even when it changes for you, it may not have yet changed for everyone worldwide.

A good thing to take note of is that it takes 24-48 hours for propagation time for most domains to point to a new server, while sometimes it can be as little as an hour or a few minutes, DNS propagation is based on multiple factors like your location and ISP and is not something anyone has any real control over.

http://support.hostgator.com/article...ng-propagation
http://support.hostgator.com/article...pagation-times

[beiker]

Also another thing that you could do here is to do an NSLOOKUP. Still on the same window, CMD, type "nslookup www.yoursite.com". Results are like this.

nslookup www.google.com
Server: vnsc-bak.sys.gtei.net
Address: 4.2.2.2

Non-authoritative answer:
Name: www.l.google.com
Addresses: 74.125.71.106
74.125.71.147
74.125.71.99
74.125.71.103
74.125.71.104
74.125.71.105
Aliases: www.google.com

I'm using 4.2.2.2 as a DNS server. It could be different from yours. And your domain may also resolve one IP address.

[mrintech]

I hope someone finds this information useful: Access your Website before DNS Propagation

[GvilleRick]

Originally Posted by mrintech

I hope someone finds this information useful: Access your Website before DNS Propagation

The suggestions at that link will work for accessing the site before propagation or for testing before the nameservers are changed. I would suggest making a note, however, to remove the entries from the HOSTS file after propagation to prevent problems should the IP change. I can remember working for quite a while with one customer who was unable to access their site when they added an SSL certificate. We had to change the IP and they had the old IP in their HOSTS file so the site worked fine for everyone but the client.

[mrintech]

Originally Posted by GvilleRick

The suggestions at that link will work for accessing the site before propagation or for testing before the nameservers are changed. I would suggest making a note, however, to remove the entries from the HOSTS file after propagation to prevent problems should the IP change. I can remember working for quite a while with one customer who was unable to access their site when they added an SSL certificate. We had to change the IP and they had the old IP in their HOSTS file so the site worked fine for everyone but the client.

Thanks