#!/bin/sh

   ##########################################################
  #                                                         #
 #           Written 6/18/08 by Jeff Schroeder            # #
##########################################################  #
#                                                        #  #
# pushnamedconf.sh - Push out a script to update the     #  #
#                    named.conf and run it.              #  # 
#                                                        #  #
#                                                        # #
##########################################################
# $Id: pushnamedconf.sh 68111 2008-10-13 22:19:41Z jschroeder $

TIMEOUT=15 # Seconds before initial connection times out
MASTER_DNS_SERVER=master.dns.server # VIP for master dns server
MASTER_DATACENTER=$(echo $MASTER_DNS_SERVER | awk -F. '{print $2}')
MASTER_DNS=$(host -t A $MASTER_DNS_SERVER | awk '{print $NF}')
SYNC_SCRIPT="$(which bindconfsync-slave.sh)"
SSH_OPTIONS="-o ConnectTimeout=$TIMEOUT -o PasswordAuthentication=no"

usage() {
    cat << EOF >&2
Usage: $(basename $0) [OPTIONS]
Push out bindconfsync-slave.sh to all nameservers to update named.conf
                       -l - List servers
                       -c [CLUSTER] - Only push changes to [CLUSTER]
                       -p - Only push changes to primary servers ie: ns1.*.mtt
                       -b - Only push changes to backup servers  ie: ns2.*.mtt
                       -n - Display what would happen but don't actually do it
EOF
    exit 1
}

# To get a new list of CLUSTERS, run this command:
# awk -F'["]' '/zone.*mtt/{if ($2 ~ ".mtt$" && $2 !~ "core" ) print $2}' /var/named/chroot/etc/named.conf
# Strip out clusters that don't have local dns servers

CLUSTERS="chi01
chi02
dub01
fra01
lax01
lax02
lon01
lon02
nyc01
nyc02
nyc04
nyc05
nyc06
sin01
tyo01"

# getopts is braindumb about gnu style options
if [ "$1" = "--help" ]; then
    usage
fi
# Do some sanity checks on the script used to sync the named.conf
if [ ! -x "$SYNC_SCRIPT" -a -e "$SYNC_SCRIPT" ]; then
    chmod 755 "$SYNC_SCRIPT"
elif [ ! -e "$SYNC_SCRIPT" ]; then
    echo "FATAL: $SYNC_SCRIPT missing" >&2
    exit 1
fi

while getopts 'pbnlhc:' opt; do
    case "$opt" in
        p) PATTERN='^ns1\.'   ;;
        b) PATTERN='^ns2\.'   ;;
        l) LIST=true          ;;
        n) DRYRUN=true        ;;
        c) CLUSTERS="$OPTARG" ;;
        h) usage              ;;
        *) usage              ;;
    esac
done

for cluster in $CLUSTERS ; do
    if [ "$cluster" = "$MASTER_DATACENTER" ]; then
        echo "${HOSTNAME:-$(hostname -f)}: Skipping $MASTER_DATACENTER" >&2
        continue
    fi
    dns_servers="$dns_servers $(host -l ${cluster}.mtt $MASTER_DNS | 
                                egrep "${PATTERN:-^ns[12]\.}" | \
                                awk '{if ($1 ~ "^ns") print $1}' | \
                                sed -e 's/ /\n/g' | \
                                grep -v '^$')"
done

# Show a prompt if no arguments are given. This prevents accidents
if [ $# -eq 0 ]; then
    echo "Pushing changes to these dns servers:"
    printf "%s\n" $dns_servers
    until [ ! -z "$input" ]; do
        echo -n "Are you sure you want to continue? y/n: "
        read input
    done
    input=$(echo $input | tr [A-Z] [a-z] | cut -c1)

    # Exit on anything that doesn't start with y
    [ "$input" = "y" ] || exit 1
fi

if [ ! -z "$LIST" ]; then
    echo "Pushing changes to these dns servers:"
    printf "%s\n" $dns_servers
    exit 0
fi

if [ ! -z "$DRYRUN" ]; then
    scp="echo scp"
    ssh="echo ssh"
else
    scp=scp
    ssh=ssh
fi

for server in $dns_servers; do
    tput init
    if [ ! "$DRYRUN" ]; then
        echo "${HOSTNAME:-$(hostname -f)}: pushing configuration out to $server"
    fi

    $scp -q $SSH_OPTIONS "$SYNC_SCRIPT" root@${server}:$SYNC_SCRIPT
    $ssh -t $SSH_OPTIONS -l root $server "$SYNC_SCRIPT" 2>&1 | \
    egrep -v 'Connection to.*closed.'
done