Dns host a records not updating
NOTE: make sure to remove the entries added to 'hosts' file 48 hours later when the nameservers are fully propagated.
It is also possible to check your website content during the DNS propagation with the help of proxy services (for instance, this one) that will allow you to access websites anonymously. How to check if DNS propagation has completed for you?
Without these records, a member computer can’t authenticate and get the information it needs to operate in the domain.
It then acts like a teenager who can’t get the car keys, growing sullen and exhibiting a variety of bad behaviors. Let’s say you’re a VAR with a customer you plan to upgrade from NT 4.0 to Windows 2000 Server or Windows Server 2003.
When you update the nameservers for a domain, it may take up to 24-48 hours for the change to take effect. In other words, it is a period of time ISP (Internet service provider) nodes across the world take to update their caches with the new DNS information of your domain. Let’s imagine you live in Bari, Italy, and you just have changed the nameservers for your domain that is hosted in Phoenix, USA.
That is why the new nameservers will not propagate immediately – ISPs have different cache refreshing intervals, so some of them will still have the old DNS information in the memory.
There is no definitive way to tell when propagation is complete for you as it depends on three factors: TTL, your ISP and geographical location.
However, you may use online DNS checkers in order to track if the DNS record information propagated against multiple nameservers located in different parts of the world.
As a result, your domain will be resolved to your previous host from the places where the propagation has not been completed yet and to a new one – from the places where it has already passed. So your computer starts by checking local DNS cache, then the request is sent to your local Bari ISP. How to check if DNS propagation has completed for you? Due to DNS caches of different levels, after the nameservers change, some of your visitors might still be directed to your old server for some time, whereas others can see the website from the new server shortly after the change. When you open your domain in a web browser, your request is not going to the hosting server directly, it has to pass through several ISP nodes first.If it's the IP address of the new server, probably, the DNS propagation is complete for you.
If the IP address belongs to the old server, you need to wait for the DNS propagation to complete.
This guide will help you to get the general information about DNS propagation and provide you with the answers to the following questions: 1. If it is not there, it looks it up and saves it in order to speed up the loading next time and to reduce the traffic.