| 1 | .TH DCM 8 "30 Nov 1988" "Project Athena" |
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| 2 | \" RCSID: $HeadURL: svn+ssh://svn.mit.edu/moira/trunk/moira/man/dcm.8 $ $Id: dcm.8 3956 2010-01-05 20:56:56Z zacheiss $ |
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| 3 | .SH NAME |
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| 4 | dcm, startdcm \- build config files from Moira database and update servers |
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| 5 | .SH SYNOPSIS |
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| 6 | .B dcm |
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| 7 | [servicename ...] |
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| 8 | .br |
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| 9 | .B startdcm |
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| 10 | .SH DESCRIPTION |
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| 11 | The |
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| 12 | .B dcm |
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| 13 | must be run periodically on the Moira server. Rather than invoke |
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| 14 | .B dcm |
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| 15 | directly, one generally runs |
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| 16 | .B startdcm, |
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| 17 | which starts the dcm running in the proper working directory and |
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| 18 | captures logging messages. |
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| 19 | .PP |
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| 20 | The |
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| 21 | .B dcm |
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| 22 | may be disabled by the presence of the file |
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| 23 | .I /etc/nodcm |
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| 24 | or by setting the value of |
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| 25 | .I dcm_enable |
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| 26 | to zero in the Moira database. Logging is done to standard output. |
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| 27 | If critical errors are detected, they are logged to |
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| 28 | .B /moira/critical.log |
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| 29 | and in a zephyrgram to class |
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| 30 | .B Moira |
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| 31 | instance |
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| 32 | .B DCM |
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| 33 | in addition to standard output. |
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| 34 | .PP |
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| 35 | For the actual generation of config files, the |
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| 36 | .B dcm |
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| 37 | will fork off generator programs of the form |
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| 38 | .B /moira/bin/\fIservice\fB.gen. |
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| 39 | Each generator takes as an argument the name of the output file to |
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| 40 | produce. Many of them also require working directories in |
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| 41 | .B /moira/dcm/\fIservice\fB. |
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| 42 | A generator exits with a status code defined in |
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| 43 | .I <mr_et.h>. |
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| 44 | In particular, |
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| 45 | .B MR_NO_CHANGE |
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| 46 | is a common exit status if the database hasn't changed since the last |
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| 47 | time this generator was run. |
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| 48 | .PP |
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| 49 | .B startdcm |
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| 50 | sets its working directory to the root, disconnects from the terminal |
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| 51 | and puts itself in the background. It then starts |
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| 52 | .B /moira/bin/dcm, |
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| 53 | and will capture lines the dcm writes to standard output and log them |
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| 54 | in |
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| 55 | .B /moira/dcm.log |
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| 56 | along with a timestamp. |
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| 57 | .B startdcm |
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| 58 | will also log the exit status of the |
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| 59 | .B dcm |
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| 60 | if it is non-zero. |
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| 61 | .SH FILES |
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| 62 | /moira/dcm.log |
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| 63 | .br |
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| 64 | /moira/critical.log |
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| 65 | .br |
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| 66 | /moira/bin/*.gen \- service file generators will be searched for |
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| 67 | here. |
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| 68 | .br |
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| 69 | /tmp/tkt_dcm \- temporary Kerberos ticket storage. |
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| 70 | .br |
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| 71 | /etc/athena/srvtab \- The dcm must be able to get Kerberos tickets for "sms" |
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| 72 | (null instance). |
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| 73 | .SH "SEE ALSO" |
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| 74 | The Project Athena Technical Plan section on Moira. |
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| 75 | |
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