xref: /openbsd-src/sbin/resolvd/resolvd.8 (revision f5291493f82d538e1c1c2f0b06fed2a3c1439aaf)

.\"	$OpenBSD: resolvd.8,v 1.12 2023/02/21 07:47:24 jmc Exp $
.\"
.\" Copyright (c) 2021 Florian Obser <florian@openbsd.org>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
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.Dd $Mdocdate: February 21 2023 $
.Dt RESOLVD 8
.Os
.Sh NAME
.Nm resolvd
.Nd a daemon to handle nameserver configuration
.Sh SYNOPSIS
.Nm
.Op Fl dv
.Sh DESCRIPTION
.Nm
handles the contents of
.Pa /etc/resolv.conf ,
which contains details of the system's DNS nameservers, and is
read by the resolver routines in the C library.
Nameservers are learned from various sources, incorporated in a priority
order, then user-edited information found in the pre-existing file is
re-appended.
.Pp
.Nm
checks whether
.Xr unwind 8
is running and, if so, places a nameserver line at the top
to cause local resolution:
.Pp
.Dl nameserver 127.0.0.1
.Pp
.Nm
also monitors the routing socket for proposals learned by
.Xr dhcpleased 8 ,
.Xr iked 8 ,
.Xr slaacd 8 ,
or network devices which natively learn DNS information such as
.Xr sppp 4
or
.Xr umb 4 .
Proposals can be sent manually using the
.Xr route 8
.Cm nameserver
command.
The proposals are added in priority order,
but commented out if
.Xr unwind 8
is running.
.Pp
After that,
.Nm
appends all user-edited lines found in the file.
.Pp
.Nm
also notices if the
.Pa /etc/resolv.conf
file is edited, and will rewrite the file, re-blending the various
pieces of information.
It will also create
.Pa /etc/resolv.conf
if it does not exist or if it is empty.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl d
Do not daemonize.
If this option is specified,
.Nm
will run in the foreground and log to
.Em stderr .
.It Fl v
Produce more verbose output.
.El
.Sh SEE ALSO
.Xr resolv.conf 5 ,
.Xr dhcpleased 8 ,
.Xr route 8 ,
.Xr slaacd 8 ,
.Xr unwind 8
.Sh HISTORY
The
.Nm
program first appeared in
.Ox 6.9 .