iankelling.org Git - automated-distro-installer/blob - pxe-server

   1 #!/bin/bash
   2 # Copyright (C) 2016 Ian Kelling
   3
   4 # This program is free software; you can redistribute it and/or
   5 # modify it under the terms of the GNU General Public License
   6 # as published by the Free Software Foundation; either version 2
   7 # of the License, or (at your option) any later version.
   8
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program; if not, write to the Free Software
  16 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17
  18 # Setup dhcp server to point to tftp server,
  19 # and depending on the type, setup the tftp server.
  20
  21 # usage: $0 TYPE
  22 # default distro is the base debian/fedora type. others are fai & arch.
  23 # for no pxe server, use a no-op like : or true.
  24
  25 set -eE -o pipefail
  26 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
  27
  28
  29 usage() {
  30     cat <<EOF
  31 Usage: ${0##*/} [OPTIONS] [HOST TYPE]
  32 Configure dnsmasq pxe server options and fai-chboot if appropriate.
  33
  34
  35 Without HOST TYPE, disable pxe server and fai server.
  36 TYPE is one of arch, plain, fai.
  37 HOST is a hostname known to the dhcp server, or default for all
  38 Note, when switching between plain and arch, you will need to
  39 do something like:
  40 ssh wrt
  41 cd /mnt/usb
  42 rm tftpboot
  43 ln -s <arch/debian iso dir> tftpboot
  44
  45
  46 -r         Don't redeploy fai config. For example, if there is a different host
  47            that is mid-install.
  48
  49 -a         Don't setup pxe, just Wait for 2 dhcp acks, then disable the pxe
  50            server after a delay.  First ack is for pxe boot, 2nd ack is
  51            for os boot. Sometimes on debian, there is a 3rd one shortly
  52            after the 2nd. I can't remember exactly why this caused a
  53            problem, but I'm hoping the sleep will take care of it.
  54
  55 -w         Setup pxe, then wait like -a.
  56 -h|--help  Print help and exit
  57
  58
  59 Note: Uses GNU getopt options parsing style
  60 EOF
  61     exit $1
  62 }
  63
  64 ##### begin command line parsing ########
  65
  66 redep=true
  67 acks=2
  68 wait=false
  69 temp=$(getopt -l help harw "$@") || usage 1
  70 eval set -- "$temp"
  71 while true; do
  72     case $1 in
  73         -a) wait=true; set=false; shift ;;
  74         -r) redep=false; shift ;;
  75         -w) wait=true; set=true; shift ;;
  76         -h|--help) usage ;;
  77         --) shift; break ;;
  78         *) echo "$0: Internal error!" ; exit 1 ;;
  79     esac
  80 done
  81
  82 read -r host type <<<"$@"
  83
  84 case $# in
  85     0|2);;
  86     *)
  87         echo "$0: error: expected 0 or 2 arguments"
  88         echo
  89         usage 1
  90         ;;
  91 esac
  92
  93 if [[ $host ]]; then
  94     host_tag="tag:$host,"
  95 fi
  96
  97 ##### end command line parsing ########
  98
  99 e() {
 100     echo "$@"
 101     "$@"
 102 }
 103
 104 arch() {
 105     cat <<EOF
 106 dhcp-option-force=209,boot/syslinux/archiso.cfg
 107 dhcp-option-force=210,/arch/
 108 dhcp-boot=${host_tag}/arch/boot/syslinux/lpxelinux.0
 109 EOF
 110 }
 111
 112 plain() {
 113     # if arch was used before, this additionally needs
 114     # the tftp link in /mnt/usb to be changed.
 115     cat <<EOF
 116 dhcp-boot=${host_tag}pxelinux.0
 117 EOF
 118 }
 119
 120 fai() {
 121     cat <<EOF
 122 dhcp-boot=${host_tag}pxelinux.0,faiserver.lan,faiserver.lan
 123 EOF
 124 }
 125
 126 ack-wait() {
 127     wait_count=$1
 128     if [[ $host ]]; then
 129         host_regex=" $host"
 130     fi
 131     regex=".*DHCPACK.*$host_regex$"
 132     i=0
 133     while (( i != wait_count )) && read -r line; do
 134         if [[ $line =~ $regex ]]; then
 135             i=$((i+1))
 136             echo $line
 137         fi
 138     done < <(ssh wrt logread -f)
 139     e sleep 20
 140 }
 141
 142 set-pxe() {
 143     ${type:-:}|ssh wrt "cedit pxe /etc/dnsmasq.conf || /etc/init.d/dnsmasq restart
 144 $([[ $type == arch ]] && echo arch-pxe-mount)"
 145 }
 146
 147
 148 if $set; then
 149     set-pxe
 150     if [[ $type == fai ]]; then
 151         e myfai-chboot $host
 152         if $redep; then
 153             e fai-redep
 154         fi
 155     else
 156         # This will fail if faiserver is not setup, so ignore any
 157         # failure and don't bother us about it.
 158         myfai-chboot &>/dev/null ||:
 159     fi
 160 fi
 161
 162 if $wait; then
 163     # fai's debian jessie 8.5ish does 2 dhcp requests when booting,
 164     # roughly 4 seconds apart. Earlier
 165     # versions did just 1. Now testing on a vm, it does 1.
 166     # bleh.
 167     echo "waiting for $acks dhcp acks then disabling pxe"
 168     ack-wait $acks
 169     type=
 170     set-pxe
 171
 172     # previously tried waiting for one more ack then disabling faiserver,
 173     # since it can contain sensitive info, so turn it off when not in use,
 174     # but disabling that for now as it's inconvenient to clean this
 175     # up and run it in the background etc.
 176
 177     # if [[ $type == fai ]]; then
 178     #     echo "waiting for 1 dhcp ack then disabling fai server"
 179     #     ack-wait 1
 180     #     faiserver-disable
 181     # fi
 182 fi