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         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  67             MESSAGE=$"Reverting /etc/resolv.conf"
  68             dialog "$MESSAGE"
  69             if [ -f "/etc/plc_resolv.conf" ] ; then
  70                 ourfile=$(grep "$SIGNATURE" /etc/plc_resolv.conf| wc -l)
  71                 if [ $ourfile -ne 0 ] ; then
  72                     dialog "WARNING: original /etc/resolv.conf was generated by etc/plc.d/dns"
  73                 fi
  74                 mv -f /etc/plc_resolv.conf /etc/resolv.conf
  75             fi
  76             check
  77             result ""
  78             MESSAGE=$"Removing /etc/plc_hosts"
  79             dialog "$MESSAGE"
  80             [ -f "/etc/plc_hosts" ] && rm -f /etc/plc_hosts
  81             result ""
  82         fi
  83         if [ $PLC_DNS_ENABLED -eq 0 -a -f "/etc/resolv_plc.backup" ] ; then
  84             MESSAGE="Restoring /etc/resolv.conf"
  85             dialog "$MESSAGE"
  86             mv -f /etc/resolv_plc.backup /etc/resolv.conf
  87             result ""
  88         fi
  89
  90         if [ $PLC_DNS_ENABLED -eq 1 ] ; then
  91             MESSAGE="Stopping DNS server"
  92             dialog "$MESSAGE"
  93             killproc plc_dnsmasq
  94             check
  95             result ""
  96         fi
  97
  98         ;;
  99 esac
 100
 101 exit $ERRORS