.TH ADSRV 8 
.SH NAME
adsrv \- Plan B volume announce server
.SH SYNOPSIS
.B adsrv
[
.B -d
]
[
.B -n
.I addr
]
[
.B -c
.I volcfg
]
[
.I dir
]
.SH DESCRIPTION
.I Adsrv
is a registry service for Plan B volumes. Volumes
register with it to announce availability, names and properties, and
.I bns
tries to reach this service to learn of publicly available volumes.
.PP
The program runs at the central file server, so that all other machines
can know where to find it. This service uses an ad-hoc protocol to
register and to discover volumes.
.PP
The protocol maintains connections
open between file servers and
.I adsrv
that are initially used the file servers to write descriptions of their volumes
in the format required by
.IR bns (4).
While the connection is alive,
.I adsrv
keeps a copy of the announce at
.B /lib/ndb/vol
or at
.I dir
when it is specified. When the connection breaks, the announce is
forgotten and the corresponding file with the copy is removed.
.PP
Connections between
.I bns
and
.I adsrv
are used by the former to ask for the set of known announces, which are
sent using the standard description format for the volume spec. See
.IR bns (4).
.PP
Option
.B -c
tells
.I adsrv
to read
.I volcfg
to find announces for static volumes (which are always there).
.PP
Option
.B -n
can be used to give an alternate address to listen for client requests.
The default address is
.B tcp!*!11010
and is assumed to be available at the file server.
.PP
Flag
.B -d
enables diagnostic messages for debugging.
.SH SOURCE
.B /sys/src/cmd/adsrv.c
.SH "SEE ALSO"
.IR bns (4),
.IR planbfs (4).
.SH BUGS
Connections are not authenticated.
Anyone can lie.