What is DNS propagation?
DNS propagation is a complex process for updating any new changes in the Domain Name System (DNS). In addition, it distributes them all over the network.
Constant changes on the DNS are required frequently, especially if you own a business online or manage a network. Some of the possible scenarios are adding, deleting, updating a DNS record. In another case, you could want to change a particular TTL (Time-to-Live) value, include an SSL certificate, or redirect your visitors to a subdomain. Maybe, you want to route your email. There are a lot of circumstances that could occur and require DNS modification.
How much time does DNS propagation usually take?
However, no matter what type of change you want to make, it is going to be stored on the authoritative DNS server. Yet, there are numerous DNS servers on the entire network, for instance, the recursive DNS servers. They are placed all over the world, and each of them has to receive the changes and modifications you made. If that does not happen your visitors are going to experience some difficulties. In addition, each of these servers is a fundamental piece of the DNS resolution process.
Factors affecting DNS propagation
It takes from hours to days to completely propagate DNS changes, and several factors could affect DNS propagation time.
TTL (Time-to-Live) of the DNS records. Usually, servers store the DNS records for some time before scanning for an update. Therefore, the adjustments you made are going to be propagated entirely until these TTLs expire.
User’s device DNS cache. After a user visits a website, its device stores in its cache memory the DNS records. Again, it depends on the TTL value for how long. Before that value expires, customers are going to attempt to reach an old IP address before the modification you executed. As soon as the TTL of the cache expires, the DNS propagation is going to be initiated.
TTL of the Internet service providers (ISPs) servers.
TTLs values on the ISP servers are estimated separately from yours. Typically, ISPs set servers’ TTL for a longer period of time to handle DNS traffic and manage their servers’ resources. To speed up the response, they also cache DNS records of domains. So, your DNS changes are going to propagate until the TTL of the ISP server expires.
DNS hierarchy changes. The TTLs of the Root servers are usually established for more extended periods, for instance, two days or more. The reason for that is to prevent stress due to the severe use.
How to check it?
Check DNS propagation depending on your OS in these two ways.
Windows
If you are a Windows user, first, you will have to open the Command Prompt. There you can utilize the Nslookup command for your website.
nslookup domain.com
*Just replace domain.com with your domain name.
That way, you perform a lookup for an A or AAAA record. It has to show the IP addresses for your website. Then you can examine if they have already up to date.
macOS and Linux
If you are a macOS/Linux user, you can utilize the dig command. First, open the Terminal on your device. Then, type the following:
dig domain.com
You are going to get a similar result to the Nslookup command on Windows OS. That is the A or AAAA record and the current IP addresses.
*Just replace domain.com with your domain name.