path: root/abs/core/diskless-legacy/config_diskless_frontend.bash

#!/bin/bash
# This script configures your backend so that a diskless
# frontend can boot from it.

function backtitle() { # no arguments.
  BT="${0##*/}"
  KMV='/etc/LinHES-release'
  if [ -f "$KMV" ]; then
    BT="-= $(cat $KMV) $BT =-"
  fi
}

function must_be_root() { # no arguments.
  test $(id -u) == 0 && return
  MSG="\Z1ERROR\Zn: This script \Z4should\Zn be run by \Z1root\Zn."
  dialog --backtitle "$BT" --colors --msgbox "$MSG" 5 45
  exit 4
}

backtitle 
must_be_root

TITLE="Diskless FE Configuration"
DOPTS=(--backtitle "$BT" --title "$TITLE" --trim --aspect 30 )

DAEMON_LOG=/var/log/daemon.log
BOOT_DEFAULT=/tftpboot/pxelinux.cfg/default

unable_to_determine_mac_for_default_fe ()
{
  if dialog "${DOPTS[@]}" --yes-label "Boot FE and try again" \
       --no-label "Delete $fe_nfsroot" \
       --yesno "Unable to automatically determine the MAC address of
       the current default frontend by interrogating $DAEMON_LOG.
       This may be because you have not yet booted the diskless FE. You can
       either boot the diskless FE and try running $0 again, or delete
       $fe_nfsroot and re-create it later." 0 0 ; then
    exit
  else
    rm -Rf $fe_nfsroot $BOOT_DEFAULT
  fi
  exit
}

find_existing_diskless_fes() {

  unset frontend_names
  unset frontend_nfsroots
  unset frontend_ips
  unset frontend_macs

  for frontend_config in $(ls /tftpboot/pxelinux.cfg 2> /dev/null) ; do

    frontend_name=$(basename $(
      grep append /tftpboot/pxelinux.cfg/$frontend_config |
      sed -e 's/.*nfsroot=//' | awk -F, '{print $1}' | awk -F/ '{print $NF}'))
    frontend_nfsroot=$(
      grep append /tftpboot/pxelinux.cfg/$frontend_config |
      cut -d ':' -f 2 | cut -d ',' -f 1)
    frontend_ip=\
$((0x${frontend_config:0:2})).$((0x${frontend_config:2:2})).\
$((0x${frontend_config:4:2})).$((0x${frontend_config:6:2}))
    frontend_mac=$(
      cat /etc/dhcpd.conf |
      grep "host $frontend_name" |
      sed 's/hardware ethernet /#/g' |
      cut -d '#' -f 2 |
      cut -d ';' -f 1)

    if [ -n "$frontend_name" -a -n "$frontend_nfsroot" -a \
         -n "$frontend_ip" -a -n "$frontend_mac" ] ; then
      frontend_names=( "${frontend_names[@]}" $frontend_name )
      frontend_nfsroots=( "${frontend_nfsroots[@]}" $frontend_nfsroot )
      frontend_ips=( "${frontend_ips[@]}" $frontend_ip )
      frontend_macs=( "${frontend_macs[@]}" $frontend_mac )
    fi
  done

echo frontend_names="${frontend_names[@]}"
echo frontend_nfsroots="${frontend_nfsroots[@]}"
echo frontend_ips="${frontend_ips[@]}"
echo frontend_macs="${frontend_macs[@]}"

}

check_for_default_fe () {
  # This function looks to see if there is a diskless FE that has only been
  # partially configured (i.e. it's MAC address has not been determined and
  # as a result it has not been allocated a fixed IP.

  if [ -e $BOOT_DEFAULT ] ; then
      # There is a $BOOT_DEFAULT config file that has not yet been set to a
      # fixed IP address. See if we can interrogate the log files to
      # determine what the MAC adderss of the FE is so that we can turn it
      # into a fixed ip node. This is the first step in allowing multiple
      # diskless frontends.

      # First determine from the default file, the nfsroot that it is for.

      fe_nfsroot=$(grep append $BOOT_DEFAULT | cut -d ':' -f 2 | cut -d ',' -f 1)

      if [ -z "$fe_nfsroot" ] ; then
        echo "Unable to determine the location of the nfsroot from" \
          $BOOT_DEFAULT
        exit
      fi

      echo fe_nfsroot=$fe_nfsroot

      # Now determine the IP address by looking for an instance in the
      # daemon log file for which the specified nfsroot was mounted.

      fe_ipaddress=$(
        grep "authenticated mount request from " $DAEMON_LOG |
        grep $fe_nfsroot |
        tail -1 |
        sed 's/authenticated mount request from /#/g' |
        cut -d '#' -f 2 |
        cut -d ':' -f 1)

      echo fe_ipaddress=$fe_ipaddress

      unset fe_macaddress

      if [ ! -z "$fe_ipaddress" ] ; then
        fe_macaddress=$(
          grep "DHCPACK on $fe_ipaddress" $DAEMON_LOG |
          tail -1 |
          sed 's/DHCPACK on '$fe_ipaddress' to /#/g' |
          cut -d '#' -f 2 |
          cut -d ' ' -f 1)
      fi

      echo fe_macaddress=$fe_macaddress

      if [ -z "$fe_macaddress" ] ; then
        unable_to_determine_mac_for_default_fe
      else
        if ! dialog "${DOPTS[@]}" --yesno "By interrogating $DAEMON_LOG,
                it appears that the $(basename $fe_nfsroot) frontend was
                last used by a host with MAC Address of $fe_macaddress which
                was allocated IP address $fe_ipaddress.
                Do you wish to allocate the IP to that host (so that you
                can configure another diskless FE)?" 0 0 ; then
          dialog "${DOPTS[@]}" --msgbox "Boot the correct diskless FE and
            run $0 again." 0 0
          exit
        fi

        # Setup dhcpd.conf so that the FE's MAC address always uses a fixed
        # ip address and the PXE configuration is fixed for that address.

        hex_ip_address=$(printf "%02X%02X%02X%02X" $(echo $fe_ipaddress |
          tr '.' ' '))
        echo hex_ip_address=$hex_ip_address
        mv -fv $BOOT_DEFAULT $(dirname $BOOT_DEFAULT)/$hex_ip_address

        cp -f /etc/dhcpd.conf /etc/dhcpd.conf.bak
        cat /etc/dhcpd.conf.bak |
          grep -v "host $(basename $fe_nfsroot)" > \
          /etc/dhcpd.conf
        echo "\
host $(basename $fe_nfsroot) \
{hardware ethernet $fe_macaddress; fixed-address $fe_ipaddress;}" \
          >> /etc/dhcpd.conf

        /sbin/sv restart dhcpd

        dialog "${DOPTS[@]}" --msgbox "The frontend $(basename $fe_nfsroot)
          with a MAC address of $fe_macaddress and an nfsroot directory of
          $fe_nfsroot has been configured with a fixed IP address of
          $fe_ipaddress." 0 0
        exit
      fi
  fi

}

get_network_interface() {
  NETDEVICES="$(cat /proc/net/dev |
    awk -F: '/ath.:|wlan.:|eth.:|tr.:/{print $1}')"
  echo NETDEVICES=$NETDEVICES
  NUM_DEVICES=$(echo $NETDEVICES | wc -w)
  echo NUM_DEVICES=$NUM_DEVICES
  if [ $NUM_DEVICES = 1 ] ; then
    INTERFACE=$NETDEVICES
  else
    DEVICELIST=""
    DEVNUM=0
    for DEVICE in $NETDEVICES
    do
      DEVNUM=$(($DEVNUM + 1))
      DEVICELIST="$DEVICELIST $DEVICE Interface${DEVNUM} "
    done
    echo DEVICELIST=$DEVICELIST
    TMP=/tmp/interface
    rm -Rf $TMP
    dialog "${DOPTS[@]}" --menu "Which network interface?" 18 70 12 \
      $DEVICELIST 2>$TMP || exit
    INTERFACE=$(cat $TMP)
  fi
  echo INTERFACE=$INTERFACE
}

validip(){
  echo "$1" | egrep -q -e '[0-9]+\.[0-9]+\.[0-9]+.[0-9]+'
  return $?
}

get_network_info() {
  BACKEND_IP=$(echo $(ifconfig $INTERFACE | grep "inet addr" | tr ':' ' ') |
    cut -d ' ' -f 3)
  echo BACKEND_IP=$BACKEND_IP
  NAMESERVERS="$(awk '/^nameserver/{printf "%s ",$2}' /etc/resolv.conf)"
  echo NAMESERVERS=$NAMESERVERS
  GATEWAY="$(LANG=C LC_ALL=C route -n | awk '/^0\.0\.0\.0/{print $2; exit}')"
  echo GATEWAY=$GATEWAY
  NETWORK="${BACKEND_IP%.*}"
  echo NETWORK=$NETWORK
  HOST="${BACKEND_IP##*.}"
  echo HOST=$HOST
  NETMASK="$(LANG=C LC_ALL=C ifconfig $INTERFACE |
    awk '/[Mm]ask/{FS="[:   ]*";$0=$0; print $8; exit}')"
  echo NETMASK=$NETMASK

  # See if we can determine the range of IP addresses currently allowed in
  # dhcpd.conf

  IPRANGE=( $(grep ^[[:space:]]*range /etc/dhcpd.conf |
              sed 's/range//g' | tr -d ';') )

  echo ${IPRANGE[@]}
  if [ $(echo ${IPRANGE[@]} | wc -w) -eq 2 ] ; then
    START=$(echo ${IPRANGE[0]} | tr '.' '\t' | cut -f 4)
    END=$(echo ${IPRANGE[1]} | tr '.' '\t' | cut -f 4)
    echo START=$START
    echo END=$END
  fi

  # Could not

  if [ -z "$START" -o -z "$END" ] ; then
    if [ "$HOST" -lt "20" ] ; then
      START=21
      END=26
    else
      START=11
      END=16
    fi
  fi

  IPRANGE_FROM=""
  IPRANGE_TO=""

  while [ -z "$IPRANGE_FROM" -o -z "$IPRANGE_TO" -o -z "$IPRANGE" ]
  do
    IPRANGE="$NETWORK.$START $NETWORK.$END"
    rm -f /tmp/iprange

    if ! dialog "${DOPTS[@]}" --clear --inputbox "Please enter the desired
           IP-Range of addresses that should be allocated by clients,
           separated by a single space." 10 75 "$IPRANGE" \
           2> /tmp/iprange ; then
      exit
    fi

    IPRANGE=$(cat /tmp/iprange)
    echo IPRANGE=$IPRANGE
    IPRANGE_FROM="${IPRANGE%% *}"
    IPRANGE_TO="${IPRANGE##* }"

    for i in "$IPRANGE_FROM" "$IPRANGE_TO"
    do
      validip "$i" || IPRANGE=""
    done
  done
}

setup_dhcpd() {
  # Generate dhcpd.conf from template

  if [ ! -f /etc/dhcpd.conf.orig ] ; then
    mv -f /etc/dhcpd.conf /etc/dhcpd.conf.orig
  fi

  ALLNAMESERVERS=""
  for i in $NAMESERVERS; do
    ALLNAMESERVERS="${ALLNAMESERVERS:+$ALLNAMESERVERS,} $i"
  done
  echo ALLNAMESERVERS=$ALLNAMESERVERS

  cat >/etc/dhcpd.conf <<EOT
# dhcpd.conf for LinHES Diskless Frontend

# global settings
## POF allow booting;
allow bootp;
default-lease-time 600;
max-lease-time 7200;

subnet ${NETWORK}.0 netmask ${NETMASK} {
  next-server $BACKEND_IP;
  filename "pxelinux.0";
  option subnet-mask ${NETMASK};
  range ${IPRANGE_FROM} ${IPRANGE_TO};
  ${ALLNAMESERVERS:+option domain-name-servers $ALLNAMESERVERS;}
  ${GATEWAY:+option routers $GATEWAY;}
}
EOT

  for (( fe = 0 ; fe < ${#frontend_names[@]} ; fe++ )) ; do
    echo "host ${frontend_names[$fe]} \
{hardware ethernet ${frontend_macs[$fe]}; \
fixed-address ${frontend_ips[$fe]};}" >> \
      /etc/dhcpd.conf
  done

  /sbin/add_service.sh dhcpd
}

setup_tftpd() {
  /sbin/add_service.sh tftpd
}

check_delete_of_existing_nfsroot() {
  if [ -d $NFSROOT ] ; then
    if dialog "${DOPTS[@]}" --yesno "\
There is already a directory $NFSROOT. Do you want to delete it and \
rebuild it from scratch?" 10 70 ; then
      echo Deleting $NFSROOT
      rm -Rf $NFSROOT
    else
      echo "OK then, bye."
      exit
    fi
  fi
}

enable_mysql_and_backend_networking() {
  # Enable mysql networking on the backend.

  /sbin/sv stop mythbackend

  if grep -q ^skip-networking /etc/my.cnf ; then
    echo "Commenting out skip-networking."
    cp /etc/my.cnf /etc/my.cnf~
    cat /etc/my.cnf~ | sed 's/^skip-networking/#skip-networking/g' > \
      /etc/my.cnf
    /sbin/sv restart mysql
  else
    echo "Already commented out skip-networking."
  fi

  # Make sure that the backend ip settings in the mythtv mysql database have
  # the actual IP address of the backend rather than the loopback address.
  # Otherwise the frontend will not be able to connect to the backend.

  echo "Setting backend IP in mythtv's mysql settings"
  echo "
UPDATE settings SET data='$BACKEND_IP' WHERE value='BackendServerIP';
UPDATE settings SET data='$BACKEND_IP' WHERE value='MasterServerIP';" |
    mysql mythconverg

  /sbin/sv start mythbackend
}

export_mounts() {
  # Ensure that the /myth directory is exported.

  if ! grep -q ^/myth[[:space:]] /etc/exports ; then
    echo "Adding line for /myth in /etc/exports"
    echo "/myth *(rw,async,no_subtree_check)" >> /etc/exports
  else
    echo "Already added line for /myth in /etc/exports"
  fi

  if ! grep -q ^/data/var/cache/pacman[[:space:]] /etc/exports ; then
    echo "Adding line for /data/var/cache/pacman in /etc/exports"
    echo "/data/var/cache/pacman *(rw,async,no_subtree_check)" >> /etc/exports
  else
    echo "Already added line for /data/var/cache/pacman in /etc/exports"
  fi

  # Ensure that the montpoints that are used as storage groups are exported.

  for storage_mount in ${storage_mounts[@]} ; do

    if ! grep -q ^${storage_mount}[[:space:]] /etc/exports ; then
      echo "Adding line for ${storage_mount} in /etc/exports"
      echo "${storage_mount} *(rw,async,no_subtree_check)" >> /etc/exports
    else
      echo "Already added line for ${storage_mount} in /etc/exports"
    fi
  done
}

find_storage_mounts() {
  unset storage_mounts
  for group in $(mysql -sB mythconverg -e \
    "select dirname from storagegroup where hostname = '$(hostname)'") ; do

    group_mount=$group
    while ! mountpoint -q $group_mount ; do
      group_mount=$(dirname $group_mount)
    done

    echo Storage group $group mountpoint is $group_mount
    storage_mounts=( "${storage_mounts[@]}" $group_mount )
  done
}

enable_nfs() {
  /sbin/add_service.sh nfsd
}

restart_nfs (){
  /usr/sbin/exportfs -arv
}

export_nfsroot() {
  # Ensure that the NFSROOT directory is appropriately exported.

  if ! grep -q ^$NFSROOT[[:space:]] /etc/exports ; then
    echo "Adding line for $NFSROOT in /etc/exports"
    echo "$NFSROOT *(rw,no_root_squash,async,no_subtree_check)" >> /etc/exports
  else
    echo "Already added line for $NFSROOT in /etc/exports"
  fi
}

create_tftpboot_directory() {
  # Create the directory with the tftp stuff.

  echo "Creating /tftpboot directories"
  mkdir -p /tftpboot/pxelinux.cfg

  if [ ! -e /tftpboot/pxelinux.0 ] ; then
   cp -fv /usr/lib/syslinux/pxelinux.0 /tftpboot/pxelinux.0
  fi

  if [ ! -e /tftpboot/vmlinuz26 ] ; then
    cp -fv /boot/vmlinuz26 /tftpboot/vmlinuz26
  fi

  if [ ! -e /tftpboot/kernel26.img ] ; then

    echo "Building kernel miniroot"
#    if [ -z "$(awk -F\" '$1 ~ /^MODULES=/ && $2 ~ /nfs/' /etc/mkinitcpio.conf)" ] ; then
#      cp /etc/mkinitcpio.conf /etc/mkinitcpio.conf~
#      sed -e '/^MODULES=/s/\"$/ nfs\"/' < /etc/mkinitcpio.conf~ > /etc/mkinitcpio.conf
#    fi
    if [ -z "$(awk -F\" '$1 ~ /^HOOKS=/ && $2 ~ /net/' /etc/mkinitcpio.conf)" ] ; then
      cp /etc/mkinitcpio.conf /etc/mkinitcpio.conf~
      sed -e '/^HOOKS=/s/\"$/ net\"/' < /etc/mkinitcpio.conf~ > /etc/mkinitcpio.conf
    fi
    /sbin/mkinitcpio -g /tftpboot/kernel26.img
  fi
}

create_default_pxelinux_entry() {
  echo "\
  default linux

  label linux
  kernel vmlinuz26
  append initrd=kernel26.img rootfstype=nfs root=/dev/nfs nfsroot=$BACKEND_IP:$NFSROOT,v3,rsize=16384,wsize=16384 init=/sbin/runit ip=dhcp" \
    > /tftpboot/pxelinux.cfg/default
}

create_new_nfsroot() {
  # Prompt the user for the name of the NFSROOT.

  FRONTEND=
  NFSROOT=

  while [ -z "$FRONTEND" ] ; do
    if ! dialog "${DOPTS[@]}" --inputbox "Enter the hostname of the new
           diskless FE:" 0 0 2> /tmp/frontend_hostname ; then
      exit
    fi

    FRONTEND=$(cat /tmp/frontend_hostname)
  done

  # Prompt the user for the location of the NFSROOT.

  while [ -z "$NFSROOT" ] ; do
    NFSROOT=/nfsroot/$FRONTEND

    if ! dialog "${DOPTS[@]}" --clear --inputbox "Enter the location of the
           NFSROOT for the diskless FE:" \
           0 0 "$NFSROOT" 2> /tmp/nfsroot_location ; then
      exit
    fi

    NFSROOT=$(cat /tmp/nfsroot_location)
  done

  check_delete_of_existing_nfsroot

  # Create the nfsroot directory that the FE will use as its root filesystem.

  echo "Creating the $NFSROOT directory."
  mkdir -p $NFSROOT
  for DIR in /* ; do
    if [[ "$DIR" != /mnt && \
          "$DIR" != /data && \
          "$DIR" != /media && \
          "$DIR" != /tmp && \
          "$DIR" != /etc.old && \
          "$DIR" != /storage && \
          "$DIR" != /var && \
          "$DIR" != /nfsroot && \
          "$DIR" != /tftpboot && \
          "$DIR" != /cdrom ]]
    then
      if mountpoint -q $DIR && [ "$DIR" != "/dev" ] ; then
        echo "  Making mountpoint dir $DIR"
        cd $NFSROOT
        tar c $DIR --exclude=$DIR/* 2> /dev/null | tar x 2> /dev/null
      else
        echo "  Copying $DIR to $NFSROOT"
        cp -ax $DIR $NFSROOT
      fi
    fi
  done

  cd $NFSROOT

  # Exclude specific bits of /var

  tar c /var \
    --exclude=/var/lib/dhcpcd \
    --exclude=/var/lib/locate \
    --exclude=/var/lib/mlocate \
    --exclude=/var/lib/named \
    2> /dev/null | tar x 2> /dev/null

  for DIR in /mnt /data /tmp /media /cdrom /var/lib/mlocate ; do
    echo "  Creating $DIR"
    tar c $DIR --exclude=$DIR/* 2> /dev/null | tar x 2> /dev/null
  done

  mkdir -p $NFSROOT/data/var/cache/pacman

  chroot $NFSROOT /sbin/remove_service.sh dhcpd
  chroot $NFSROOT /sbin/remove_service.sh lighttpd
  chroot $NFSROOT /sbin/remove_service.sh mysql
  chroot $NFSROOT /sbin/remove_service.sh mythbackend
  chroot $NFSROOT /sbin/remove_service.sh nfsd
  chroot $NFSROOT /sbin/remove_service.sh nmbd
  chroot $NFSROOT /sbin/remove_service.sh smbd
  chroot $NFSROOT /sbin/remove_service.sh tftpd
  chroot $NFSROOT /sbin/remove_service.sh avahi

  # Update the fstab.

  cp $NSFROOT/etc/fstab $NFSROOT/etc/fstab~
  cat $NFSROOT/etc/fstab~ | grep -v ext[34] | grep -v xfs |
    grep -v ^UUID= > $NFSROOT/etc/fstab

  echo "\
$BACKEND_IP:/nfsroot / nfs defaults,nolock,auto,noatime 0 2
$BACKEND_IP:/myth /myth nfs defaults,nolock,auto,noatime 0 0
$BACKEND_IP:/data/var/cache/pacman /data/var/cache/pacman nfs defaults,nolock,auto,noatime 0 0
" >> $NFSROOT/etc/fstab

  for storage_mount in ${storage_mounts[@]} ; do
    echo "\
$BACKEND_IP:${storage_mount} ${storage_mount} nfs auto,noatime,nolock,rsize=32768,wsize=32768 0 0" \
    >> $NFSROOT/etc/fstab
  done

  cp $NFSROOT/etc/rc.sysinit $NFSROOT/etc/rc.sysinit~
  sed -e '/^\/sbin\/minilogd/s/$/\n\n# Mount NFS early\n\/bin\/mount -a -t nfs/' \
    < $NFSROOT/etc/rc.sysinit~ > $NFSROOT/etc/rc.sysinit

  # Update networking

  echo $FRONTEND > $NFSROOT/etc/hostname

  cp $NFSROOT/etc/hosts $NFSROOT/etc/hosts~
  echo "127.0.0.1 $FRONTEND localhost" > $NFSROOT/etc/hosts
  cat $NFSROOT/etc/hosts~ | grep -v 127.0.0.1 >> $NFSROOT/etc/hosts

  cp $NFSROOT/etc/net/ifaces/eth0/options $NFSROOT/etc/net/ifaces/eth0/options~
  sed -e 's/^BOOTPROTO=.*/BOOTPROTO=none/' < $NFSROOT/etc/net/ifaces/eth0/options~ \
    > $NFSROOT/etc/net/ifaces/eth0/options

  # Update mysql settings

  cp /usr/share/mythtv/mysql.txt $NFSROOT/home/mythtv/.mythtv/mysql.txt

  if grep -q DBHostName=localhost $NFSROOT/home/mythtv/.mythtv/mysql.txt ; then
    echo "Setting database host in frontend's mysql.txt."
      cp $NFSROOT/home/mythtv/.mythtv/mysql.txt \
         $NFSROOT/home/mythtv/.mythtv/mysql.txt.orig
      cat $NFSROOT/home/mythtv/.mythtv/mysql.txt.orig |
        sed 's/DBHostName=localhost/DBHostName='$BACKEND_IP'/g' > \
        $NFSROOT/home/mythtv/.mythtv/mysql.txt
  else
    echo "Already set Database host in frontend's mysql.txt."
  fi

  chown mythtv:mythtv $NFSROOT/home/mythtv/.mythtv/mysql.txt

  # Check if the user has a diskless_tweak.<frontend_name> file in root's 
  # home directory. If they do, run it inside the chroot of the NFS root.

  if [[ -x ~/diskless_tweak.$FRONTEND ]] ; then
    echo Running tweak file ~/diskless_tweak.$FRONTEND
    chroot $NFSROOT bash -v ~/diskless_tweak.$FRONTEND
  fi

  create_default_pxelinux_entry
  export_nfsroot
  restart_nfs

  dialog "${DOPTS[@]}" --msgbox "Boot your diskless FE
  and then re-run this script ($0) so that the MAC address
  of the Diskless FE can be obtained." 0 0
}

##########################################
##########################################
##
## MAIN BODY OF SCRIPT                  ##
##
##########################################
##########################################

check_for_default_fe
find_existing_diskless_fes

get_network_interface
get_network_info
setup_tftpd
setup_dhcpd
enable_mysql_and_backend_networking
find_storage_mounts
export_mounts
create_tftpboot_directory
enable_nfs

# Restart nfs to ensure that the exported /myth directory can be mounted. This
# is required to create a new frontend.

restart_nfs

if [ ${#frontend_names[@]} -eq 0 ] ; then
  create_new_nfsroot
else
  for (( fe = 0 ; fe < ${#frontend_names[@]} ; fe++ )) ; do
    frontend_options=( "${frontend_options[@]}" \
      "${frontend_names[$fe]} (MAC:${frontend_macs[$fe]} \
IP:${frontend_ips[$fe]})" "" )
  done

echo 0=${frontend_names[0]}
echo 1=${frontend_names[1]}
echo 2=${frontend_names[2]}
echo 3=${frontend_names[3]}

  if ! dialog "${DOPTS[@]}" --menu "Select a frontend to delete or to create
         a new one." 0 0 0 "${frontend_options[@]}" \
         "New Frontend" "" 2> /tmp/selected_fe; then
    exit
  fi

  selected_option=$(cat /tmp/selected_fe)

  if [ "$selected_option" = "New Frontend" ] ; then
    create_new_nfsroot
    exit
  fi

echo $selected_option
echo ${frontend_options[0]}
echo ${frontend_options[2]}
echo ${frontend_nfsroots[@]}

  for (( fe = 0 ; fe < ${#frontend_names[@]} ; fe++ )) ; do
    if [ "$selected_option" = "${frontend_options[$(($fe*2))]}" ] ; then
      if dialog "${DOPTS[@]}" --yesno "Do you wish to delete the frontend
           with nfsroot ${frontend_nfsroots[$fe]}?" 0 0 ; then
        # Delete the nfsroot directory.
        rm -Rfv ${frontend_nfsroots[$fe]}

        # Delete the tftpboot pxe boot config file.

        hex_ip_address=$(printf "%02X%02X%02X%02X" \
          $(echo ${frontend_ips[$fe]} | tr '.' ' '))
        rm /tftpboot/pxelinux.cfg/$hex_ip_address

        # Remove reference to the frontend from the dhcp.conf
        cp -fv /etc/dhcpd.conf /etc/dhcpd.conf.bak
        grep -v "host ${frontend_names[$fe]}" /etc/dhcpd.conf.bak > \
          /etc/dhcpd.conf
        /sbin/sv restart dhcpd
      fi
    fi
  done
fi