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                 cp $rfile /etc/plc_resolv.conf
  47                 chmod 444 /etc/plc_resolv.conf
  48                 ourfile=$(grep "$SIGNATURE" /etc/resolv.conf| wc -l)
  49                 if [ $ourfile -eq 0 ] ; then
  50                     cp /etc/resolv.conf /etc/resolv.bak
  51                     echo $SIGNATURE > /etc/resolv.conf
  52                     echo nameserver 127.0.0.1 >> /etc/resolv.conf
  53                     chmod 444 /etc/resolv.conf
  54                 fi
  55             else
  56                 cp /etc/resolv.conf /etc/resolv.bak
  57                 mv -f $rfile /etc/resolv.conf
  58                 chmod 444 /etc/resolv.conf
  59             fi
  60         fi
  61
  62         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  63             plc_daemon dnsmasq
  64             check
  65         fi
  66
  67         result "$MESSAGE"
  68         ;;
  69
  70     stop)
  71         MESSAGE=$"Reverting /etc/resolv.conf"
  72         dialog "$MESSAGE"
  73         if [ -f "/etc/resolv.bak" ] ; then
  74             ourfile=$(grep "$SIGNATURE" /etc/resolv.bak | wc -l)
  75             if [ $ourfile -ne 0 ] ; then
  76                 dialog "WARNING: original /etc/resolv.conf was generated by etc/plc.d/dns"
  77             fi
  78             mv -f /etc/resolv.bak /etc/resolv.conf
  79         fi
  80         check
  81         result ""
  82         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  83             MESSAGE=$"Removing /etc/plc_hosts"
  84             dialog "$MESSAGE"
  85             [ -f "/etc/plc_hosts" ] && rm -f /etc/plc_hosts
  86             result ""
  87         fi
  88
  89         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  90             MESSAGE="Stopping DNS server"
  91             dialog "$MESSAGE"
  92             killproc plc_dnsmasq
  93             check
  94             result ""
  95         fi
  96
  97         ;;
  98 esac
  99
 100 exit $ERRORS