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 Without HOST TYPE, disable pxe server and fai server.
  35
  36 HOST       A hostname known to the dhcp server, or default for all.
  37 TYPE       One of arch, plain, fai.
  38
  39
  40 -r         Don't redeploy fai config. For example, if there is a different host
  41            that is mid-install.
  42
  43 -a         Don't setup pxe, just Wait for 2 dhcp acks, then disable the pxe
  44            server after a delay.  First ack is for pxe boot, 2nd ack is
  45            for os boot. Sometimes on debian, there is a 3rd one shortly
  46            after the 2nd. I can't remember exactly why this caused a
  47            problem, but I'm hoping the sleep will take care of it.
  48
  49 -w         Setup pxe, then wait like -a.
  50 -h|--help  Print help and exit
  51
  52
  53 Note, when switching between plain and arch, you will need to
  54 do something like:
  55 ssh wrt
  56 cd /mnt/usb
  57 rm tftpboot
  58 ln -s <arch/debian iso dir> tftpboot
  59
  60
  61 Note: Uses GNU getopt options parsing style
  62 EOF
  63     exit $1
  64 }
  65
  66 ##### begin command line parsing ########
  67
  68 redep=true
  69 acks=2
  70 wait=false
  71 temp=$(getopt -l help harw "$@") || usage 1
  72 eval set -- "$temp"
  73 while true; do
  74     case $1 in
  75         -a) wait=true; set=false; shift ;;
  76         -r) redep=false; shift ;;
  77         -w) wait=true; set=true; shift ;;
  78         -h|--help) usage ;;
  79         --) shift; break ;;
  80         *) echo "$0: Internal error!" ; exit 1 ;;
  81     esac
  82 done
  83
  84 read -r host type <<<"$@"
  85
  86 case $# in
  87     0|2);;
  88     *)
  89         echo "$0: error: expected 0 or 2 arguments"
  90         echo
  91         usage 1
  92         ;;
  93 esac
  94
  95 if [[ $host ]]; then
  96     host_tag="tag:$host,"
  97 fi
  98
  99 ##### end command line parsing ########
 100
 101 e() {
 102     echo "$@"
 103     "$@"
 104 }
 105
 106 arch() {
 107     cat <<EOF
 108 dhcp-option-force=209,boot/syslinux/archiso.cfg
 109 dhcp-option-force=210,/arch/
 110 dhcp-boot=${host_tag}/arch/boot/syslinux/lpxelinux.0
 111 EOF
 112 }
 113
 114 plain() {
 115     # if arch was used before, this additionally needs
 116     # the tftp link in /mnt/usb to be changed.
 117     cat <<EOF
 118 dhcp-boot=${host_tag}pxelinux.0
 119 EOF
 120 }
 121
 122 fai() {
 123     cat <<EOF
 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     while (( i != wait_count )) && read -r line; do
 136         if [[ $line =~ $regex ]]; then
 137             i=$((i+1))
 138             echo $line
 139         fi
 140     done < <(ssh wrt logread -f)
 141     e sleep 20
 142 }
 143
 144 set-pxe() {
 145     ${type:-:}|ssh wrt "cedit pxe /etc/dnsmasq.conf || /etc/init.d/dnsmasq restart
 146 $([[ $type == arch ]] && echo arch-pxe-mount)"
 147 }
 148
 149
 150 if $set; then
 151     set-pxe
 152     if [[ $type == fai ]]; then
 153         e myfai-chboot $host
 154         if $redep; then
 155             e fai-redep
 156         fi
 157     else
 158         # This will fail if faiserver is not setup, so ignore any
 159         # failure and don't bother us about it.
 160         myfai-chboot &>/dev/null ||:
 161     fi
 162 fi
 163
 164 if $wait; then
 165     # fai's debian jessie 8.5ish does 2 dhcp requests when booting,
 166     # roughly 4 seconds apart. Earlier
 167     # versions did just 1. Now testing on a vm, it does 1.
 168     # bleh.
 169     echo "waiting for $acks dhcp acks then disabling pxe"
 170     ack-wait $acks
 171     type=
 172     set-pxe
 173
 174     # previously tried waiting for one more ack then disabling faiserver,
 175     # since it can contain sensitive info, so turn it off when not in use,
 176     # but disabling that for now as it's inconvenient to clean this
 177     # up and run it in the background etc.
 178
 179     # if [[ $type == fai ]]; then
 180     #     echo "waiting for 1 dhcp ack then disabling fai server"
 181     #     ack-wait 1
 182     #     faiserver-disable
 183     # fi
 184 fi