Unraveling the Mysteries: My Stories of 'Why It's Always DNS?'


Hey tech enthusiasts! Today, let me take you on a journey into the world of DNS – the magic that helps us find websites on the internet. I'm a sysadmin at the second-largest ISP in Nepal, and I want to share the challenges we face with DNS in simpler terms.

1. Private IP Confusion

People get frustrated because they can't reach their favorite websites. Why? Our DNS is looking up private IPs instead of public ones. We scramble to fix it, checking for mistakes, outdated info, or issues with routing or access control.

2. Trouble with DNS Cache

The DNS cache is usually helpful, but it can get overwhelmed, causing delays. Users experience slow internet, and we're flooded with messages. We need to figure out if it's due to cache size, errors, or potential security problems.

3. BGP Downtime Drama

Imagine DNS servers taking a break because the BGP (Border Gateway Protocol) isn't playing nice with our DNS servers (BGP gone into Active Mood). We have to fix it fast without users noticing any disruptions.

4. Typos and Mistakes

A small typo can mess everything up, and we need to act quickly to fix it. We're also exploring ways to prevent these mistakes, using automation and double-checking our work.

5. Outdated Records

 Users see "This Site Can't Be Reached" or "404 Page Not Found" because our DNS records are outdated. We carefully update them without interrupting ongoing services.

6. Competitor's DNS Mystery

Users can access websites through a competitor's DNS but not ours. We play detective to find misconfigurations and routing problems, ensuring our users end up where they should.

7. Forgetting to Restart

After making DNS changes, sometimes the servers don't catch on. Sometimes, it's because we forget to reload the configuration or restart. It's also the nature of DNS, which takes time for changes to take effect.

8. Windows AD DNS Sync Issues

Our Windows Active Directory system throws us a curveball – DNS records won't sync. We troubleshoot to ensure smooth user authentication and access to resources.

9. Website Blocking Challenges – TikTok Edition

Blocking certain websites (Including Open/Public DNS like;, is a constant challenge, especially with ever-changing tech like TikTok. We adapt our strategies (Nating, Routing) to balance user restrictions and follow regulations.

In the end, being a sysadmin in the ISP world is a digital adventure and heavy frustration/pressure as well. The DNS challenges we face are not just technical problems; they're a mix of emotions. Each situation is like a chapter in our journey, where we work hard to keep the internet running smoothly for everyone. So, the next time someone asks, "Why is it always DNS?" remember, behind the scenes, a team of tech wizards is working hard to keep the digital world in harmony. Stay tuned for more stories from the world of system administration!

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