Update almost instantly and convey the updated information to all new domain/address inquires. Granted the internal systems here at bluehill.com provide prompt attention to domain/address changes the rest of the Internet is not so kind, enter propagation!

What is propagation delay?

Many users will notice that after a change is made to the domain/address information of their account that their local email/web/etc systems may still point to the old server, this evil process is known as propagation delay. It is a typical scenario inherent to the way the domain/address system works.

When a user on the Internet types in a domain their computer goes through many magical processes to find the server, it isn't really magical but it sounds much cooler, a more technical (and not as funny) run down is as follows:

• Local software (e.g. Netscape) asks OS (e.q. Windows) for address
• OS asks your ISP's name server(s) as assigned in TCP/IP or DCHP Server for address
• Your ISP's name servers ask our name server for address

Upon successful acquisition of the address for a domain name the local ISP saves the domain/address information in their caching name server. This allows the ISP to provide prompt DNS service for subsequent queries by accessing their local domain/address information for future requests without having to query the bluehill.com name servers again. This is typically a very nice robust system, which ensures prompt domain/address resolution service once the data is acquired. This can also be some what inconvenient for accounts who are in process of changing their domain/address information and want to access their new account by it's domain while the ISP still has this in it's cache. Unfortunately this is a set in stone system and will resolve itself once TTL expires!

When does TTL expire?

Ok, so we know the ISP has the old data in their system, and calling them will not do anything (assuming you can even get to them, hehe) when will this situation be resolved? Enter TTL, it serves as an expiration date to tell ISP's that after so much time they MUST re-download the zone data from our system. As documented in the official documents for running name servers this value should be between 1 day and two weeks. In order to ensure minimal transition for client sites our name servers are configured with only a 6 hour TTL! Great, so you know the change has taken place, all new visitor to your site are going to the new server, and you want to know how much longer until you (the owner) get to see the new site.

How much longer?

Thankfully the TTL expiration time on this old data can be acquired from your ISP's name servers using the interface below. It does require some information about their network but we will show you how to get that. Once the TTL value displayed by the interface below reaches zero the new data will be loaded by your ISP, yay!

How to find my ISP's name server?

This is assuming you are running Windows as your Operating System, if you are not please contact your ISP and ask them what your name servers are, they may provide you with a list in which case you will want to test all name servers provided since your connection may be using a certain one.

Click Start, run and in the dialog box type winipcfg and press ok. This will open a dialog box which shows common connection data. Press the More Info>> button at the bottom, this will open the detailed menu which shows your IP's name servers. Next to the DNS Servers label will be the address for your ISP's name server, if there is a button to the right of that with 3 dots write down each IP and click the button for the next name server until you have them all. It is a good idea to test each name server because you do not know which one is servicing your connection currently. Use the data here for the TTL Tester located at the bottom of this page.

TTL Tester

We will now proceed to ask the ISP's name server what data they have on file and for how much longer they plan to keep it.