3 ms·
> forcefully caching even failed requests to a configurable timeout I've been doing ~SRE for 1.5 years and I've worked or helped on 3 outages related to negati
by agilob 5y ago
> forcefully caching even failed requests to a configurable timeout
I've been doing ~SRE for 1.5 years and I've worked or helped on 3 outages related to negative DNS.. Please don't use negative cache, if you don't know how enough about DNS and can't monitor it
- littlecranky67 5y agoI wouldn't suggest any ISP should do that (and I am none) but probably host this for own personal usage/home networks. If recursive DNS servers go down under the load of "smart devices", having a local copy of a larger number/set of IPs I usually visit might come in handy (and none of my requests would worsen the issue of server overload).
- agilob 5y agoThis is 'cache', my OpenWRT router has this for thousands of records, but negative cache means: "remember this domain doesn't exist and don't retry asking other DNS providers". This is very dangerous. Your browser AND operating system AND router already provide DNS caching, it's not something average user should even think about. You might want to consider it when things in your ISP go wrong (hello BT), or majority of computer request the same domains frequently, but then again, your router should do it already.
- littlecranky67 5y agoWell now in retrospect, Cloudflare claims to have enabled SERVFAIL caching to mitigate, and other commenters here say their ISPs did similar. You might want to overthink the negative caching strategy.