NAME
unwind —
validating DNS resolver
SYNOPSIS
unwind |
[-dnv] [-f
file] [-s
socket] |
DESCRIPTION
unwind is a validating DNS resolver. It is intended to
run on client machines like workstations or laptops and only listens on
localhost. unwind sends DNS queries to nameservers to
answer queries and switches to resolvers learned from
dhclient(8), dhcpleased(8) or
slaacd(8) if
it detects that DNS queries are blocked by the local network. It periodically
probes if DNS is no longer blocked and switches back to querying nameservers
itself.
unwind keeps the DNS answers in a cache
shared by the different DNS name server types.
unwind manages the cache size by deleting oldest
entries when needed. The cache is non-configurable and is lost upon process
restart.
To have unwind enabled at boot time, use
“rcctl enable unwind”, which sets
unwind_flags=""in rc.conf.local(8).
A running unwind can be controlled with
the unwindctl(8) utility.
The options are as follows:
-d- Do not daemonize. If this option is specified,
unwindwill run in the foreground and log to stderr. -ffile- Specify an alternative configuration file.
-n- Configtest mode. Only check the configuration file for validity.
-ssocket- Use an alternate location for the default control socket.
-v- Produce more verbose output. Multiple
-voptions increase the verbosity. Debug output from libunbound is only available when logging to stderr.
FILES
- /etc/unwind.conf
- Default
unwindconfiguration file. - /var/db/unwind.key
- Trust anchor for DNSSEC validation.
- /dev/unwind.sock
- UNIX-domain socket used for communication with unwindctl(8).
SEE ALSO
unwind.conf(5), dhclient(8), dhcpleased(8), slaacd(8), unbound(8), unwindctl(8)
STANDARDS
P. Mockapetris, DOMAIN NAMES - CONCEPTS AND FACILITIES, RFC 1034, November 1987.
P. Mockapetris, DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION, RFC 1035, November 1987.
HISTORY
The unwind program first appeared in
OpenBSD 6.5.
AUTHORS
The unwind program was written by
Florian Obser
<florian@openbsd.org>.