3 ms·
At the time, OP likely pulled cached DNS records to interrogate the associated IPs directly for their application (HTTP) level resources.
by chrononaut 5y ago
At the time, OP likely pulled cached DNS records to interrogate the associated IPs directly for their application (HTTP) level resources.
- rbobby 5y agoAnd thinking on this... a timeout is the right answer if facebook's dns servers are missing in action.
- 1vuio0pswjnm7 5y agoTheres no need to use a cache. Even if authoritative DNS servers are unreachable, there are, for example, multiple, authorised, public scans of port 53 available for free download. There are also passive DNS datasets also available for free. While recursive caches may be convenient, IMO they are the least trustworthy sources of DNS data.