iankelling.org Git - distro-setup/blob - dynamic-ip-update.sh

   1 #!/bin/bash
   2
   3 set -eE -o pipefail
   4 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
   5
   6
   7 cur="$(host -4 b8.nz iankelling.org | sed -rn 's/.*has address (.*)/\1/p;T;q')"
   8 ip=$(curl -s4 https://iankelling.org/cgi/pubip)
   9
  10 # note, a simpler way to do this would be to ssh and use
  11 # "${SSH_CLIENT%% *}
  12 # to update bind if needed.
  13
  14 if [[ $cur != $ip ]]; then
  15     nsupdate -k /p/c/machine_specific/li/filesystem/etc/bind/Kb8.nz.*.private <<EOF
  16 server iankelling.org
  17 zone b8.nz
  18 update delete b8.nz. A
  19 update add b8.nz. 300 A $ip
  20 update delete *.b8.nz. A
  21 update add *.b8.nz. 300 A $ip
  22 show
  23 send
  24 EOF
  25 fi
  26
  27 # # persistent initial setup for this:
  28 # # create files in /a/c/machine_specific/li/filesystem/etc/bind
  29 # # note, conflink also does some group ownership stuff.
  30
  31 # mkc /p/c/machine_specific/li/filesystem/etc/bind
  32 # s dnssec-keygen -a HMAC-MD5 -b 512 -n HOST b8.nz
  33 # s chown $USER:$USER *
  34
  35 # f=key.b8.nz
  36 # cat >$f <<EOF
  37 # key b8.nz. {
  38 # algorithm HMAC-MD5;
  39 # secret "$(awk '$1 == "Key:" {print $2}' Kb8.nz.*.private)";
  40 # };
  41 # EOF
  42
  43 # chmod 640 [kK]*
  44
  45 # myunison -ob li
  46 # ssh li conflink
  47 # ssh li ser restart bind9