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 -a         Wait for 2 dhcp acks, then disable the pxe server after a delay.
  49            First ack is for pxe boot, 2nd ack is for os boot. Sometimes
  50            on debian, there is a 3rd one shortly after the 2nd. I can't remember
  51            exactly why this caused a problem, but I'm hoping the sleep
  52            will take care of it.
  53 -w         Initially setup pxe, then wait like -a.
  54 -h|--help  Print help and exit
  55
  56
  57 Note: Uses GNU getopt options parsing style
  58 EOF
  59     exit $1
  60 }
  61
  62 ##### begin command line parsing ########
  63
  64 args=()
  65 redep=true
  66 acks=2
  67 wait=false
  68 temp=$(getopt -l help harw "$@") || usage 1
  69 eval set -- "$temp"
  70 while true; do
  71     case $1 in
  72         -a) wait=true; set=false; shift ;;
  73         -r) redep=false; shift ;;
  74         -w) wait=true; set=true; shift ;;
  75         -h|--help) usage ;;
  76         --) shift; break ;;
  77         *) echo "$0: Internal error!" ; exit 1 ;;
  78     esac
  79 done
  80
  81 read host type <<<"$@"
  82
  83 case $# in
  84     0|2);;
  85     *)
  86         echo "$0: error: expected 0 or 2 arguments"
  87         echo
  88         usage 1
  89         ;;
  90 esac
  91
  92 if [[ $host ]]; then
  93     host_tag="tag:$host,"
  94 fi
  95
  96 ##### end command line parsing ########
  97
  98 e() {
  99     echo "$@"
 100     "$@"
 101 }
 102
 103 arch() {
 104     cat <<EOF
 105 dhcp-option-force=209,boot/syslinux/archiso.cfg
 106 dhcp-option-force=210,/arch/
 107 dhcp-boot=${host_tag}/arch/boot/syslinux/lpxelinux.0
 108 EOF
 109 }
 110
 111 plain() {
 112     # if arch was used before, this additionally needs
 113     # the tftp link in /mnt/usb to be changed.
 114     cat <<EOF
 115 dhcp-boot=${host_tag}pxelinux.0
 116 EOF
 117 }
 118
 119 fai() {
 120     cat <<EOF
 121 $set_host_tag
 122 dhcp-boot=${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$"
 132     i=0
 133     tmp=$(mktemp)
 134     while (( i != wait_count )) && read line; do
 135         if [[ $line =~ $regex ]]; then
 136             i=$((i+1))
 137             echo $line
 138         fi
 139     done < <(ssh wrt logread -f)
 140     e sleep 20
 141 }
 142
 143 set-pxe() {
 144     ${type:-:}|ssh wrt "cedit pxe /etc/dnsmasq.conf || /etc/init.d/dnsmasq restart
 145 $([[ $type == arch ]] && echo arch-pxe-mount)"
 146 }
 147
 148
 149 if $set; then
 150     set-pxe
 151     if [[ $type == fai ]]; then
 152         e myfai-chboot $host
 153         if $redep; then
 154             e fai-redep
 155         fi
 156     else
 157         e myfai-chboot
 158     fi
 159 fi
 160
 161 if $wait; then
 162     # fai's debian jessie 8.5ish does 2 dhcp requests when booting,
 163     # roughly 4 seconds apart. Earlier
 164     # versions did just 1. Now testing on a vm, it does 1.
 165     # bleh.
 166     echo "waiting for $acks dhcp acks then disabling pxe"
 167     ack-wait $acks
 168     type=
 169     set-pxe
 170
 171     # previously tried waiting for one more ack then disabling faiserver,
 172     # since it can contain sensitive info, so turn it off when not in use,
 173     # but disabling that for now as it's inconvenient to clean this
 174     # up and run it in the background etc.
 175
 176     # if [[ $type == fai ]]; then
 177     #     echo "waiting for 1 dhcp ack then disabling fai server"
 178     #     ack-wait 1
 179     #     faiserver-disable
 180     # fi
 181 fi