`resolvectl` - resolve domain names, IPV4 and IPv6 addresses, DNS resource records, and services; introspect and reconfigure the DNS resolver

resolvectl [OPTIONS...] {COMMAND} [NAME...]

Options you will use

status: upstream servers per link and the resolv.conf mode
query NAME: resolve through systemd-resolved; says whether it came from cache
flush-caches: drop the cache (root)
statistics: cache size, hits and misses
dns LINK SERVER...: set the servers for a link at runtime (root)

Examples

$ resolvectl status

who does this box ask

$ sudo resolvectl flush-caches

forget cached answers here - and only here

Gotchas

Flushing your cache does nothing for anyone else's resolver. TTLs are the only way to control how long other people hold an old answer.

Taught in

8.16 How a name becomes an address on Ubuntu

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