Ask HN: Why does news.Y Combinator.com use a DNS TTL of 1s?

8 points by 500ktc 1 year ago | 3 comments

This result in every page load making a DNS request.

This is a questionable technical choice, especially considering HN's status as the SaaS mecca. So it begs the question: Why?

If the goal is to be able to rapidly switch to cloudflare when under attack then surely a TTL of 600 or 60 would be sufficient whilst being more respectful of your visitors?

toomuchtodo 1 year ago |

For fast failover to the backup server. The lack of DNS caching is immaterial, lookups are cheap, network and CPU is cheap (wrt serving DNS).

It’s not a questionable technical choice (imho) based on the use case. Simplicity is the ultimate sophistication.

jsharkey 1 year ago |

NextDNS has a "Cache Boost" option that, when enabled, clamps answers to a minimum TTL to mitigate things like this. I've noticed that some Samsung IoT domains also have aggressively low TTL.

ironmagma 1 year ago |

I'm legitimately curious what environment you're in where you notice/care about the extra DNS lookup?