plc.d/dns

   1 #!/bin/bash
   2 #
   3 # priority: 850
   4 #
   5 # Start local DNS server to provide minimal DNS forward resolution for
   6 # ourselves and our nodes.
   7 #
   8 # Mark Huang <mlhuang@cs.princeton.edu>
   9 # Copyright (C) 2006 The Trustees of Princeton University
  10 #
  11 # $Id$
  12 #
  13
  14 # Source function library and configuration
  15 . /etc/plc.d/functions
  16 . /etc/planetlab/plc_config
  17
  18 SIGNATURE="; generated by /etc/plc.d/dns --- DO NOT REMOVE THIS TEXT!"
  19
  20 # Be verbose
  21 set -x
  22
  23 case "$1" in
  24     start)
  25         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  26             MESSAGE=$"Starting DNS server"
  27             dialog "$MESSAGE"
  28
  29             dns-config
  30             check
  31         fi
  32
  33         # Set up nameservers
  34         if [ -n "$PLC_NET_DNS1" -o -n "$PLC_NET_DNS2" ] ; then
  35             MESSAGE=$"Configuring resolv.conf"
  36             dialog "$MESSAGE"
  37
  38             rfile=$(mktemp)
  39             (
  40                 echo $SIGNATURE
  41                 [ -n "$PLC_NET_DNS1" ] && echo "nameserver $PLC_NET_DNS1"
  42                 [ -n "$PLC_NET_DNS2" -a "$PLC_NET_DNS1" != "$PLC_NET_DNS2" ] && echo "nameserver $PLC_NET_DNS2"
  43             ) > $rfile
  44
  45             if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  46                 ourfile=$(grep "$SIGNATURE" /etc/resolv.conf| wc -l)
  47                 if [ $ourfile -eq 0 ] ; then
  48                     cp /etc/resolv.conf /etc/plc_resolv.conf
  49                 fi
  50             else
  51                 cp /etc/resolv.conf /etc/resolv_plc.backup
  52             fi
  53             mv -f $rfile /etc/resolv.conf
  54             chmod 444 /etc/resolv.conf
  55         fi
  56
  57         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  58             plc_daemon dnsmasq
  59             check
  60         fi
  61
  62         result "$MESSAGE"
  63         ;;
  64
  65     stop)
  66         MESSAGE=$"Reverting /etc/resolv.conf and /etc/hosts"
  67         dialog "$MESSAGE"
  68         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  69             if [ -f "/etc/plc_resolv.conf" ] ; then
  70                 ourfile=$(grep "$SIGNATURE" /etc/plc_resolv.conf| wc -l)
  71                 if [ $ourfile -ne 0 ] ; then
  72                     dialog "WARNING: original /etc/resolv.conf was generated by etc/plc.d/dns"
  73                 fi
  74                 mv -f /etc/plc_resolv.conf /etc/resolv.conf
  75             fi
  76             [ -f "/etc/plc_hosts" ] && rm -f /etc/plc_hosts
  77         fi
  78         if [ $PLC_DNS_ENABLED -eq 0 -a -f "/etc/resolv_plc.backup" ] ; then
  79             mv -f /etc/resolv_plc.backup /etc/resolv.conf
  80         fi
  81
  82         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  83             MESSAGE=$"Stopping DNS server"
  84             dialog "$MESSAGE"
  85
  86             killproc plc_dnsmasq
  87             check
  88         fi
  89
  90         result "$MESSAGE"
  91         ;;
  92 esac
  93
  94 exit $ERRORS