plc.d/dns

   1 #!/bin/bash
   2 #
   3 # priority: 950
   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
  12 # Source function library and configuration
  13 . /etc/plc.d/functions
  14 . /etc/planetlab/plc_config
  15
  16 SIGNATURE="; generated by /etc/plc.d/dns --- DO NOT REMOVE THIS TEXT"
  17
  18 # Be verbose
  19 set -x
  20
  21 case "$1" in
  22     start)
  23         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  24             MESSAGE="Starting DNS server"
  25             dialog "$MESSAGE"
  26
  27             dns-config
  28             check
  29         fi
  30
  31         # Set up nameservers
  32         if [ -n "$PLC_NET_DNS1" -o -n "$PLC_NET_DNS2" ] ; then
  33             MESSAGE="Configuring resolv.conf"
  34             dialog "$MESSAGE"
  35
  36             rfile=$(mktemp)
  37             (
  38                 echo $SIGNATURE
  39                 [ -n "$PLC_NET_DNS1" ] && echo "nameserver $PLC_NET_DNS1"
  40                 [ -n "$PLC_NET_DNS2" -a "$PLC_NET_DNS1" != "$PLC_NET_DNS2" ] && echo "nameserver $PLC_NET_DNS2"
  41             ) > $rfile
  42
  43             if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  44                 ourfile=$(grep "$SIGNATURE" /etc/resolv.conf| wc -l)
  45                 if [ $ourfile -eq 0 ] ; then
  46                     cp /etc/resolv.conf /etc/plc_resolv.conf
  47                 fi
  48             else
  49                 cp /etc/resolv.conf /etc/resolv_plc.backup
  50             fi
  51             mv -f $rfile /etc/resolv.conf
  52             chmod 444 /etc/resolv.conf
  53         fi
  54
  55         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  56             plc_daemon dnsmasq
  57             check
  58         fi
  59
  60         result "$MESSAGE"
  61         ;;
  62
  63     stop)
  64         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  65             MESSAGE=$"Reverting /etc/resolv.conf"
  66             dialog "$MESSAGE"
  67             if [ -f "/etc/plc_resolv.conf" ] ; then
  68                 ourfile=$(grep "$SIGNATURE" /etc/plc_resolv.conf| wc -l)
  69                 if [ $ourfile -ne 0 ] ; then
  70                     dialog "WARNING: original /etc/resolv.conf was generated by etc/plc.d/dns"
  71                 fi
  72                 mv -f /etc/plc_resolv.conf /etc/resolv.conf
  73             fi
  74             check
  75             result ""
  76             MESSAGE=$"Removing /etc/plc_hosts"
  77             dialog "$MESSAGE"
  78             [ -f "/etc/plc_hosts" ] && rm -f /etc/plc_hosts
  79             result ""
  80         fi
  81         if [ $PLC_DNS_ENABLED -eq 0 -a -f "/etc/resolv_plc.backup" ] ; then
  82             MESSAGE="Restoring /etc/resolv.conf"
  83             dialog "$MESSAGE"
  84             mv -f /etc/resolv_plc.backup /etc/resolv.conf
  85             result ""
  86         fi
  87
  88         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  89             MESSAGE="Stopping DNS server"
  90             dialog "$MESSAGE"
  91             killproc plc_dnsmasq
  92             check
  93             result ""
  94         fi
  95
  96         ;;
  97 esac
  98
  99 exit $ERRORS