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 $1
  62 }
  63
  64 ##### begin command line parsing ########
  65
  66 args=()
  67 redep=true
  68 acks=2
  69 wait=false
  70 temp=$(getopt -l help harw "$@") || usage 1
  71 eval set -- "$temp"
  72 while true; do
  73     case $1 in
  74         -a) wait=true; set=false; shift ;;
  75         -r) redep=false; shift ;;
  76         -w) wait=true; set=true; shift ;;
  77         -h|--help) usage ;;
  78         --) shift; break ;;
  79         *) echo "$0: Internal error!" ; exit 1 ;;
  80     esac
  81 done
  82
  83 read host type <<<"$@"
  84
  85 case $# in
  86     0|2);;
  87     *)
  88         echo "$0: error: expected 0 or 2 arguments"
  89         echo
  90         usage 1
  91         ;;
  92 esac
  93
  94 if [[ $host ]]; then
  95     host_tag="tag:$host,"
  96 fi
  97
  98 ##### end command line parsing ########
  99
 100 e() {
 101     echo "$@"
 102     "$@"
 103 }
 104
 105 arch() {
 106     cat <<EOF
 107 dhcp-option-force=209,boot/syslinux/archiso.cfg
 108 dhcp-option-force=210,/arch/
 109 dhcp-boot=${host_tag}/arch/boot/syslinux/lpxelinux.0
 110 EOF
 111 }
 112
 113 plain() {
 114     # if arch was used before, this additionally needs
 115     # the tftp link in /mnt/usb to be changed.
 116     cat <<EOF
 117 dhcp-boot=${host_tag}pxelinux.0
 118 EOF
 119 }
 120
 121 fai() {
 122     cat <<EOF
 123 $set_host_tag
 124 dhcp-boot=${host_tag}pxelinux.0,faiserver.lan,faiserver.lan
 125 EOF
 126 }
 127
 128 ack-wait() {
 129     wait_count=$1
 130     if [[ $host ]]; then
 131         host_regex=" $host"
 132     fi
 133     regex=".*DHCPACK.*$host_regex$"
 134     i=0
 135     tmp=$(mktemp)
 136     while (( i != wait_count )) && read line; do
 137         if [[ $line =~ $regex ]]; then
 138             i=$((i+1))
 139             echo $line
 140         fi
 141     done < <(ssh wrt logread -f)
 142     e sleep 20
 143 }
 144
 145 set-pxe() {
 146     ${type:-:}|ssh wrt "cedit pxe /etc/dnsmasq.conf || /etc/init.d/dnsmasq restart
 147 $([[ $type == arch ]] && echo arch-pxe-mount)"
 148 }
 149
 150
 151 if $set; then
 152     set-pxe
 153     if [[ $type == fai ]]; then
 154         e myfai-chboot $host
 155         if $redep; then
 156             e fai-redep
 157         fi
 158     else
 159         e myfai-chboot
 160     fi
 161 fi
 162
 163 if $wait; then
 164     # fai's debian jessie 8.5ish does 2 dhcp requests when booting,
 165     # roughly 4 seconds apart. Earlier
 166     # versions did just 1. Now testing on a vm, it does 1.
 167     # bleh.
 168     echo "waiting for $acks dhcp acks then disabling pxe"
 169     ack-wait $acks
 170     type=
 171     set-pxe
 172
 173     # previously tried waiting for one more ack then disabling faiserver,
 174     # since it can contain sensitive info, so turn it off when not in use,
 175     # but disabling that for now as it's inconvenient to clean this
 176     # up and run it in the background etc.
 177
 178     # if [[ $type == fai ]]; then
 179     #     echo "waiting for 1 dhcp ack then disabling fai server"
 180     #     ack-wait 1
 181     #     faiserver-disable
 182     # fi
 183 fi