.TH DCM 8 "30 Nov 1988" "Project Athena"
\" RCSID: $Header: /afs/athena.mit.edu/astaff/project/moiradev/repository/moira/man/dcm.8,v 1.8 1998-05-26 18:14:11 danw Exp $
.SH NAME
dcm, startdcm \- build config files from Moira database and update servers
.SH SYNOPSIS
.B dcm
[servicename ...]
.br
.B startdcm
.SH DESCRIPTION
The
.B dcm
must be run periodically on the Moira server.  Rather than invoke
.B dcm
directly, one generally runs
.B startdcm,
which starts the dcm running in the proper working directory and
captures logging messages.
.PP
The
.B dcm
may be disabled by the presence of the file
.I /etc/nodcm
or by setting the value of
.I dcm_enable
to zero in the Moira database. Logging is done to standard output.
If critical errors are detected, they are logged to
.B /moira/critical.log
and in a zephyrgram to class
.B Moira
instance
.B DCM
in addition to standard output.
.PP
For the actual generation of config files, the
.B dcm
will fork off generator programs of the form
.B /moira/bin/\fIservice\fB.gen.
Each generator takes as an argument the name of the output file to
produce.  Many of them also require working directories in
.B /moira/dcm/\fIservice\fB.
A generator exits with a status code defined in
.I <mr_et.h>.
In particular,
.B MR_NO_CHANGE
is a common exit status if the database hasn't changed since the last
time this generator was run.
.PP
.B startdcm
sets its working directory to the root, disconnects from the terminal
and puts itself in the background.  It then starts
.B /moira/bin/dcm,
and will capture lines the dcm writes to standard output and log them
in
.B /moira/dcm.log
along with a timestamp.
.B startdcm
will also log the exit status of the
.B dcm
if it is non-zero.
.SH FILES
/moira/dcm.log
.br
/moira/critical.log
.br
/moira/bin/*.gen \- service file generators will be searched for
here.
.br
/tmp/tkt_dcm \- temporary Kerberos ticket storage.
.br
/etc/athena/srvtab \- The dcm must be able to get Kerberos tickets for "sms"
(null instance).
.SH "SEE ALSO"
The Project Athena Technical Plan section on Moira.