4 ms·
1) It's distributed. There's not a single database with all the DNS records in existence. Each zone is responsible for hosting and serving their own records. 2
by thedougd 2y ago
1) It's distributed. There's not a single database with all the DNS records in existence. Each zone is responsible for hosting and serving their own records.
2) The TTL for a DNS record can be 0.
Edit:
3) AXFR is blocked on 'most' zones. You would need this to know all the records in a zone.
- Avamander 2y agoZero TTL is insane though and most caching resolvers allow enforcing a minimum.
- ectospheno 2y agoLast year I started bumping up min ttl on dns caches a bit each week. Stopped at one hour. No one ever complained.