Last updated: August 29, 2019
Expert DNS Troubleshooting Tips + Diagnosis Tools You Can’t Do Without
DNS problems can be a headache, even if you’re experienced with web hosting.
Often, it’s difficult to tell where faults lie. DNS can take some time to propagate, so sites can appear to be up or down at the same time, depending on your physical location.
Having DNS issues? Keep reading to find out how to resolve the most commons DNS problems – and find out why DNS is so tricky in the first place.
What Is DNS?
DNS stands for Domain Name System. It’s basically a directory for the Internet that matches up domain names with IP address.
Every single website has its own IP address on the web, and computers can connect to other computers via the Internet and look up websites using their IP address.
You can visit any website by typing in its IP address into your browser’s address bar. But IP addresses are difficult for people to remember, so we use domain names instead. The DNS is the Internet’s address book: it matches up those IP addresses to their respective domain names.
Whenever you type a domain name into your browser, it connects to your Internet service provider’s (ISP’s) DNS server to look up the DNS record to find out which IP address it needs to connect to.
A DNS server is a server that runs special DNS software that looks up DNS records and performs other DNS services. There are many DNS servers around the world, but the Internet runs using 13 root servers maintained by independent agencies such as IANA (Internet Assigned Numbers Authority), ICANN (Internet Corporation for Assigned Names and Numbers), the U.S. Army Research Lab, Verisign, and others.
Understanding DNS Problems
Any website downtime is a serious issue, and can result in lost revenue and a damaged reputation for your business or website. That’s why it’s crucial to fix any errors as soon as possible. Unfortunately, the nature of DNS makes that a bit tricky.
You, your registrar, and your host all have to work together to ensure that DNS servers point visitors to the right server, so that your website will load correctly when people type your domain in their browser’s address bar.
Most Internet service providers (ISPs) run their own DNS servers that get their information from the 13 root servers, so there’s always a delay when keeping them all in sync.
This means your site can appear online for you but offline to your visitors – both at the same time.
Why Is DNS Tricky?
Because of all the moving parts and connections involved, a variety of things can go wrong with your DNS:
- Slow updates cause problems that ripple out, often misleading you as you try to fix the issue.
- Incorrect DNS settings create a slow-motion disaster that will not be immediately apparent.
- There are multiple points of failure, and it can be hard to figure out where things have gone wrong.
Troubleshooting Common Errors
The first thing you can do when faced with DNS errors is to check for the most common issues:
- Check your domain registration. Make sure your registration is up to date and paid for, and hasn’t expired. If it is, you’ll have to renew it.
- Check your nameservers. Make sure that your domain is using the correct nameservers. If you’ve recently switched your domain registrar or hosting company, this is the most likely issue. Your domain will need to point to the correct nameservers for where your website is hosted. You can check your web host’s website to find out which nameservers you should be using.
- Wait for any recent changes to propagate. Unfortunately, due to the nature of DNS servers, it can take up to 24-48 hours for any changes you make to propagate across the web. If you just corrected your nameservers, give it some time to propagate.
Tools and Resources
So how do we go about diagnosing and fixing DNS hiccups if you’re still having issues?
Luckily, there are some handy tools available around the web that can help you diagnose your DNS problems. Try using these:
- IntoDNS is a free tool that scans your DNS records and identifies any configuration issues, then generates a detailed report, making it easy to identify and address your DNS problems in a flash.
- Network Tools provides more information, including a trace to the site and information about the domain and the host.
- OpenDNS’ Cache Check tool queries your domain directly and reports the results. Best of all, this tool checks your site using all OpenDNS servers (11 in total).