iankelling.org Git - distro-setup/blob - switch-mail-host

   1 #!/bin/bash
   2 set -x
   3 set -eE -o pipefail
   4 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
   5
   6 usage() {
   7     cat <<EOF
   8 Usage: ${0##*/} OLD_HOST NEW_HOST
   9
  10 Adjust home network dns so NEW_HOST resolves locally if it is on the
  11 local network.  Turn off mail receiving on OLD_HOST, run btrbk to move
  12 mail to NEW_HOST, turn on mail receiving on NEW_HOST.
  13
  14 -w         Don't try to ssh to wrt. Should only be used in unusual network situation.
  15 -h|--help  Print help and exit.
  16
  17 Note: Uses GNU getopt options parsing style
  18 EOF
  19     exit $1
  20 }
  21
  22 ##### begin command line parsing ########
  23
  24 update_wrt=true # default
  25 temp=$(getopt -l help wh "$@") || usage 1
  26 eval set -- "$temp"
  27 while true; do
  28     case $1 in
  29         -w) update_wrt=false; shift ;;
  30         -h|--help) usage ;;
  31         --) shift; break ;;
  32         *) echo "$0: Internal error! unexpected args: $*" ; exit 1 ;;
  33     esac
  34 done
  35
  36
  37 (( $# == 2 )) || usage 1
  38
  39 old_host=$1
  40 new_host=$2
  41 source /a/bin/bash_unpublished/source-semi-priv
  42
  43 if [[ $old_host != $MAIL_HOST ]]; then
  44     read -p "warning: \$old_host != \$MAIL_HOST: $old_host != $MAIL_HOST, proceed? y/N "
  45     if [[ $REPLY != [yY] ]]; then
  46         exit 1
  47     fi
  48 fi
  49
  50 if [[ $new_host == "$HOSTNAME" ]]; then
  51     localhost_new=true
  52     new_shell=
  53 else
  54     localhost_new=false
  55     new_shell="ssh $new_host"
  56 fi
  57
  58 old_shell="ssh $old_host"
  59 if [[ $old_host == "$HOSTNAME" ]]; then
  60     old_shell=
  61 fi
  62
  63 if [[ ! $new_host || ! $old_host ]]; then
  64     echo "$0: bad args. see script"
  65     exit 1
  66 fi
  67
  68 at_home=false
  69 if [[ $HOSTNAME == tp ]] || [[ $HOSTNAME == frodo ]] || timeout -s 9 5 ssh wrt.b8.nz :; then
  70     at_home=true
  71 fi
  72 echo "$0: at_home = $at_home"
  73
  74 source /a/bin/bash_unpublished/source-semi-priv
  75 #### begin convert private hostnames to public hostnames ####
  76 if ! $at_home; then
  77     for var in old_host new_host; do
  78         case ${!var} in
  79             tp)
  80                 eval $var=$HOME_DOMAIN
  81                 ;;
  82         esac
  83     done
  84 fi
  85 ####  end convert private hostnames to public hostnames ####
  86
  87
  88 # because our port forward is not robust enough, we can't use proxy command,
  89 # todo: setup vpn so this is all taken care of.
  90 if ! $update_wrt; then
  91     wrt_shell=:
  92 elif $at_home; then
  93     wrt_shell="ssh wrt.b8.nz"
  94 else
  95     if [[ $old_host == iank.vpn.office.fsf.org || $new_host == iank.vpn.office.fsf.org ]]; then
  96         wrt_shell="ssh iank.vpn.office.fsf.org ssh wrt.b8.nz"
  97     else
  98         wrt_shell="ssh $HOME_DOMAIN ssh wrt.b8.nz"
  99     fi
 100 fi
 101
 102 btrbk_test="systemctl is-active btrbk.service"
 103 while $new_shell $btrbk_test || $old_shell $btrbk_test; do
 104     echo "$0: btrbk is running on new or old host. sleeping for 8 seconds"
 105     sleep 6
 106     echo "$0: testing for btrbk activity in 2 seconds"
 107     sleep 2
 108 done
 109
 110 ########### end initial processing, begin actually modifying things ##########
 111
 112 restore_new_btrbk=false
 113 if $new_shell systemctl is-active btrbk.timer; then
 114     $new_shell sudo systemctl stop btrbk.timer
 115     restore_new_btrbk=true
 116 fi
 117 restore_old_btrbk=false
 118 if $old_shell systemctl is-active btrbk.timer; then
 119     $old_shell sudo systemctl stop btrbk.timer
 120     restore_old_btrbk=true
 121 fi
 122
 123 for ((i=0; i<10; i++)); do
 124     $old_shell killall arbtt-capture || break
 125     sleep 1
 126     if [[ i == 9 ]]; then
 127         warn="WARNING!!! failed to kill arbtt-capture"
 128         fi
 129     done
 130
 131
 132 $new_shell bash -s <<'EOF'
 133 set -eE
 134 if mountpoint /m; then sudo umount /m; fi
 135 if mountpoint /o; then sudo umount /o; fi
 136 EOF
 137
 138 # if new_host is not on home network, make mail.iankelling.org not resolve
 139 # on the home network.
 140 if [[ $new_host == $HOSTNAME ]] && ! $at_home; then
 141     echo | $wrt_shell cedit mail_host /etc/hosts || [[ $? == 1 ]] # 1 means file changed.
 142 else
 143     $wrt_shell bash -s <<EOFOUTER
 144     cedit mail_host /etc/hosts <<EOF || /etc/init.d/dnsmasq restart
 145 \$(grep "\b$new_host\b" /etc/hosts | awk '{print \$1}') mail.iankelling.org
 146 EOF
 147 EOFOUTER
 148 fi
 149
 150 mail-setup() {
 151     shell="$1"
 152     $shell sed -ri "s/MAIL_HOST=.*/MAIL_HOST=$new_host/" /a/bin/bash_unpublished/source-semi-priv
 153     $shell /a/bin/distro-setup/mail-setup exim4
 154 }
 155
 156 mail-setup "$old_shell"
 157
 158 sudo dd of=/etc/btrbk.conf <<'EOF'
 159 ssh_identity /root/.ssh/home
 160 # Just a guess that local7 is a good facility to pick.
 161 # It's a bit odd that the transaction log has to be logged to
 162 # a file or syslog, while other output is sent to std out.
 163 # The man does not mention a way for them to be together, but
 164 # I dunno if setting a log level like warn might also output
 165 # transaction info.
 166 transaction_syslog local7
 167
 168 # so we only run one at a time
 169 lockfile                   /var/lock/btrbk.lock
 170
 171 # default format of short does not accomidate hourly preservation setting
 172 timestamp_format long-iso
 173
 174 # only make a snapshot if things have changed
 175 snapshot_create onchange
 176 # I could make this different from target_preserve,
 177 # if one disk had less space.
 178 # for now, keeping them equal.
 179 snapshot_preserve 36h 14d 8w 24m
 180 snapshot_preserve_min 4h
 181 snapshot_dir btrbk
 182
 183 # so, total backups = ~89
 184 target_preserve 36h 14d 8w 24m
 185 target_preserve_min 4h
 186
 187 # if something fails and it's not obvious, try doing
 188 # btrbk -l debug -v dryrun
 189
 190
 191 EOF
 192
 193
 194 if $localhost_new; then
 195     btrbk_src=ssh://$old_host/mnt/root
 196     btrbk_dst=/mnt/root/btrbk
 197 else
 198     btrbk_src=/mnt/root
 199     btrbk_dst=ssh://$new_host/mnt/root/btrbk
 200 fi
 201
 202 sudo tee -a /etc/btrbk.conf <<EOF
 203 volume $btrbk_src
 204 subvolume o
 205 target send-receive $btrbk_dst
 206 EOF
 207
 208
 209 sudo btrbk -l debug --progress run
 210 $new_shell mount-latest-subvol
 211
 212 mail-setup "$new_shell"
 213
 214 if $restore_new_btrbk; then
 215     $new_shell sudo systemctl start btrbk.timer
 216 fi
 217 if $restore_old_btrbk; then
 218     $old_shell sudo systemctl start btrbk.timer
 219 fi
 220
 221 $new_shell DISPLAY=:0 arbtt-capture --sample-rate=10 &
 222
 223 echo $warn