iankelling.org Git - distro-setup/blob - btrbk-run

   1 #!/bin/bash
   2 # Copyright (C) 2016 Ian Kelling
   3
   4 # Licensed under the Apache License, Version 2.0 (the "License");
   5 # you may not use this file except in compliance with the License.
   6 # You may obtain a copy of the License at
   7
   8 #     http://www.apache.org/licenses/LICENSE-2.0
   9
  10 # Unless required by applicable law or agreed to in writing, software
  11 # distributed under the License is distributed on an "AS IS" BASIS,
  12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 # See the License for the specific language governing permissions and
  14 # limitations under the License.
  15
  16 set -eE -o pipefail
  17 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
  18
  19 [[ $EUID == 0 ]] || exec sudo -E "$BASH_SOURCE" "$@"
  20
  21 usage() {
  22     echo "top of script file:"
  23     sed -n '1,/^[# ]*end command line/{p;b};q' "$0"
  24     exit $1
  25 }
  26
  27 script_dir=$(dirname $(readlink -f "$BASH_SOURCE"))
  28
  29 # note q is owned by root:1000
  30 # note p/m is owned 1000:1000 and chmod 700
  31
  32
  33 mountpoints=()
  34
  35 rsync_mountpoint=/q
  36
  37 conf_only=false
  38 dry_run=false # mostly for testing
  39 resume_arg=
  40 rate_limit=no
  41 verbose=false
  42
  43 default_args_file=/etc/btrbk-run.conf
  44 if [[ -s $default_args_file ]]; then
  45     set -- $(< $default_args_file) "$@"
  46 fi
  47
  48 temp=$(getopt -l help cl:m:nprt:vh "$@") || usage 1
  49 eval set -- "$temp"
  50 while true; do
  51     case $1 in
  52         # only creates the config file, does not run btrbk
  53         -c) conf_only=true; shift ;;
  54         -l) rate_limit=$2; shift 2 ;;
  55         -m) IFS=, mountpoints=($2); unset IFS; shift 2 ;;
  56         -n) dry_run=true; dry_run_arg=-n; shift ;;
  57         -p) progress_arg="--progress"; shift ;;
  58         # btrbk arg: Resume only. Skips snapshot creation.
  59         -r) resume_arg=-r; shift ;;
  60         # empty is valid for just doing local snapshot. we have default hosts
  61         # we will populate
  62         -t) IFS=, targets=($2); unset IFS; shift 2 ;;
  63         -v) verbose=true; verbose_arg=-v; shift ;;
  64         -h|--help) usage ;;
  65         --) shift; break ;;
  66         *) echo "$0: Internal error!" ; exit 1 ;;
  67     esac
  68 done
  69
  70 if [[ -s $default_args_file ]]; then
  71     echo "$0: warning: default btrbk-run options set in $default_args_file (sleeping 5 seconds):"
  72     cat $default_args_file
  73     sleep 5
  74 fi
  75
  76 echo -e "$0: options: conf_only=$conf_only\ndry_run=$dry_run\nresume_arg=$resume_arg\nrate_limit=$rate_limit\nverbose=$verbose"
  77
  78 # set default targets
  79 if [[ ! -v targets ]]; then
  80     case $HOSTNAME in
  81         x2)
  82             if [[ $HOSTNAME == "$MAIL_HOST" ]]; then
  83                 targets=($HOME_DOMAIN)
  84             fi
  85             ;;
  86         tp)
  87             targets=(frodo)
  88             if [[ $HOSTNAME == "$MAIL_HOST" ]]; then
  89                 if timeout -s 9 10 ssh x2 :; then
  90                     targets+=(x2)
  91                 fi
  92             fi
  93             ;;
  94         frodo)
  95             targets=()
  96             ;;
  97         *)
  98             echo "$0: error: no default targets for this host, use -t"
  99             exit 1
 100             ;;
 101     esac
 102 fi
 103
 104 echo "targets: ${targets[*]}"
 105
 106
 107
 108 if (( ${#mountpoints[@]} )); then
 109     for mp in ${mountpoints[@]}; do
 110         if [[ -e /nocow/btrfs-stale/$mp ]]; then
 111             echo "$0: warning: $mp stale. Sleeping for 3 seconds in case you want to cancel."
 112             sleep 3
 113         fi
 114     done
 115 else # set default mountpoints
 116     if [[ $HOSTNAME == frodo ]]; then
 117         prospective_mps=(/i)
 118     else
 119         prospective_mps=(/a /q)
 120         if [[ $HOSTNAME == "$MAIL_HOST" ]]; then
 121             prospective_mps+=(/o)
 122         fi
 123     fi
 124     for mp in ${prospective_mps[@]}; do # default mountpoints to sync
 125         if [[ -e /nocow/btrfs-stale/$mp ]]; then
 126             echo "$0: warning: $mp stale, not adding to default mountpoints"
 127             continue
 128         fi
 129         if awk '{print $2}' /etc/fstab | grep -xF $mp &>/dev/null; then
 130             mountpoints+=($mp)
 131         fi
 132     done
 133 fi
 134
 135 echo "mountpoints: ${mountpoints[*]}"
 136
 137 ##### end command line parsing ########
 138
 139 rsync-dirs() {
 140     local host=$1
 141     local path=$2
 142     m rsync $dry_run_arg -ahi --relative --delete "$path" "root@$host:/"
 143 }
 144
 145 vol-conf() {
 146     cat >>/etc/btrbk.conf <<EOF
 147 volume $vol
 148 EOF
 149 }
 150 sub-conf() {
 151     cat >>/etc/btrbk.conf <<EOF
 152 subvolume $sub
 153 EOF
 154 }
 155 tg-conf() {
 156     cat >>/etc/btrbk.conf <<EOF
 157 target send-receive ssh://$tg$vol/btrbk
 158 EOF
 159 }
 160 m() { printf "%s: %s\n" "${0##*/}" "$*";  "$@"; }
 161
 162
 163 if ! which btrbk &>/dev/null; then
 164     echo "$0: error: no btrbk binary found"
 165 fi
 166
 167 cat >/etc/btrbk.conf <<EOF
 168 ssh_identity /root/.ssh/home
 169 # Just a guess that local7 is a good facility to pick.
 170 # It's a bit odd that the transaction log has to be logged to
 171 # a file or syslog, while other output is sent to std out.
 172 # The man does not mention a way for them to be together, but
 173 # I dunno if setting a log level like warn might also output
 174 # transaction info.
 175 transaction_syslog local7
 176
 177 # so we only run one at a time
 178 lockfile                   /var/lock/btrbk.lock
 179
 180 # default format of short does not accomidate hourly preservation setting
 181 timestamp_format long-iso
 182
 183 # only make a snapshot if things have changed
 184 snapshot_create onchange
 185 # I could make this different from target_preserve,
 186 # if one disk had less space.
 187 # for now, keeping them equal.
 188 snapshot_preserve 36h 14d 8w 24m
 189 snapshot_preserve_min 4h
 190 snapshot_dir btrbk
 191
 192 # so, total backups = ~89
 193 target_preserve 36h 14d 8w 24m
 194 target_preserve_min 4h
 195
 196 # if something fails and it's not obvious, try doing
 197 # btrbk -l debug -v dryrun
 198
 199 rate_limit $rate_limit
 200 EOF
 201
 202
 203 # if our mountpoints are from stale snapshots,
 204 # it doesn't make sense to do a backup.
 205 check-subvol-stale ${mountpoints[@]} || exit 1
 206
 207 for tg in ${targets[@]}; do
 208     # for an initial run, btrbk requires the dir to exist
 209     ssh root@$tg mkdir -p /mnt/root/btrbk
 210 done
 211
 212
 213 for m in ${mountpoints[@]}; do
 214     # for /i, some special cases. there is just one static target and direction.
 215     if [[ $m == /i ]]; then
 216         vol=/mnt/iroot
 217         vol-conf
 218         sub=i
 219         sub-conf
 220         tg=frodo
 221         vol=/mnt/root
 222         tg-conf
 223     else
 224         vol=/mnt/root
 225         vol-conf
 226         sub=${m##*/}
 227         sub-conf
 228         for tg in ${targets[@]}; do
 229             tg-conf
 230         done
 231     fi
 232 done
 233
 234
 235 # todo: umount first to ensure we don't have any errors
 236 # todo: do some kill fuser stuff to make umount more reliable
 237
 238
 239 if $conf_only; then
 240     exit
 241 fi
 242
 243 if $dry_run; then
 244     m btrbk -v -n $resume_arg run
 245 else
 246     # -q and just using the syslog option seemed nice,
 247     # but it doesn't show when a send has a parent and when it doesn't.
 248     m btrbk $verbose_arg $progress_arg $resume_arg run
 249 fi
 250
 251 # if we have it, sync to systems which don't
 252 if mountpoint $rsync_mountpoint >/dev/null; then
 253     for tg in ${targets[@]}; do
 254         case $tg in
 255             tp|li|lk)
 256                 for x in /p/c/machine_specific/*.hosts; do
 257                     if grep -qxF $tg $x; then
 258                         dir=${x%.hosts}
 259                         rsync-dirs $tg $dir
 260                     fi
 261                 done
 262                 ;;
 263         esac
 264     done
 265 fi
 266
 267 if ! $dry_run; then
 268     m $script_dir/mount-latest-remote ${targets[@]}
 269 fi
 270
 271
 272 # todo: move variable data we don't care about backing up
 273 # to /nocow and symlink it.
 274
 275
 276 # background on btrbk timezones. with short/long, timestamps use local time.
 277 # for long, if your local time moves backwards, by moving timezones or
 278 # for an hour when daylight savings changes it, you will temporarily get
 279 # a more aggressive retention policy for the overlapping period, and
 280 # vice versa for the opposite timezone move. The alternative is using
 281 # long-iso, which puts timezone info into the timestamp, which means
 282 # that instead of shifting time, you shift the start of day/week/month
 283 # which is used for retention to your new local time, which means for
 284 # example, if you moved forward by 8 hours, the daily/weekly/monthly
 285 # retention will be 8 hours more aggressive since midnight is at a new
 286 # time, unless you fake the timzeone using the TZ env variable.
 287 # However, in the short term, there will be no inconsistencies.
 288 # I don't see any problem with shifting when the day starts for
 289 # retention, so I'm using long-iso.
 290
 291 # note to create a long-iso timestamp: date +%Y%m%dT%H%M%S%z