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
  17 # todo: remove old leaf subvols, like keep up to 1 month or something.
  18 # todo: if we cancel in the middle of a btrfs send, then run again immediately, the received subvolume doesn't get a Received UUID: field, and we won't mount it. Need to figure out a solution that will fix this.
  19
  20 set -eE -o pipefail
  21 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
  22
  23 [[ $EUID == 0 ]] || exec sudo -E "$BASH_SOURCE" "$@"
  24
  25 usage() {
  26   echo "top of script file:"
  27   sed -n '1,/^[# ]*end command line/{p;b};q' "$0"
  28   exit $1
  29 }
  30
  31 script_dir=$(dirname $(readlink -f "$BASH_SOURCE"))
  32
  33 # note q is owned by root:1000
  34 # note p/m is owned 1000:1000 and chmod 700
  35
  36
  37 mountpoints=()
  38
  39 rsync_mountpoint=/q
  40
  41 conf_only=false
  42 dry_run=false # mostly for testing
  43 resume_arg=
  44 rate_limit=no
  45 verbose=false
  46
  47 default_args_file=/etc/btrbk-run.conf
  48 if [[ -s $default_args_file ]]; then
  49   set -- $(< $default_args_file) "$@"
  50 fi
  51
  52 temp=$(getopt -l help cl:m:nprt:vh "$@") || usage 1
  53 eval set -- "$temp"
  54 while true; do
  55   case $1 in
  56     # only creates the config file, does not run btrbk
  57     -c) conf_only=true; shift ;;
  58     -l) rate_limit=$2; shift 2 ;;
  59     -m) IFS=, mountpoints=($2); unset IFS; shift 2 ;;
  60     -n) dry_run=true; dry_run_arg=-n; shift ;;
  61     -p) progress_arg="--progress"; shift ;;
  62     # btrbk arg: Resume only. Skips snapshot creation.
  63     -r) resume_arg=-r; shift ;;
  64     # empty is valid for just doing local snapshot. we have default hosts
  65     # we will populate
  66     -t) IFS=, targets=($2); unset IFS; shift 2 ;;
  67     -v) verbose=true; verbose_arg=-v; shift ;;
  68     -h|--help) usage ;;
  69     --) shift; break ;;
  70     *) echo "$0: Internal error!" ; exit 1 ;;
  71   esac
  72 done
  73
  74 if [[ -s $default_args_file ]]; then
  75   echo "$0: warning: default btrbk-run options set in $default_args_file (sleeping 5 seconds):"
  76   cat $default_args_file
  77   sleep 5
  78 fi
  79
  80 echo -e "$0: options: conf_only=$conf_only\ndry_run=$dry_run\nresume_arg=$resume_arg\nrate_limit=$rate_limit\nverbose=$verbose"
  81
  82 # set default targets
  83 if [[ ! -v targets ]]; then
  84   case $HOSTNAME in
  85     x2|kw)
  86       if [[ $HOSTNAME == "$MAIL_HOST" ]]; then
  87         targets=($HOME_DOMAIN)
  88       fi
  89       ;;
  90     tp)
  91       targets=(frodo)
  92       if [[ $HOSTNAME == "$MAIL_HOST" ]]; then
  93         if timeout -s 9 10 ssh x2 :; then
  94           targets+=(x2)
  95         fi
  96       fi
  97       ;;
  98     frodo)
  99       targets=()
 100       ;;
 101     *)
 102       echo "$0: error: no default targets for this host, use -t"
 103       exit 1
 104       ;;
 105   esac
 106 fi
 107
 108 echo "targets: ${targets[*]}"
 109
 110
 111
 112 # set default mountpoints
 113 case $HOSTNAME in
 114   frodo)
 115     prospective_mps=(/i)
 116     ;;
 117   *)
 118     prospective_mps=(/a /q)
 119     if [[ $HOSTNAME == "$MAIL_HOST" ]]; then
 120       prospective_mps+=(/o)
 121     fi
 122     ;;
 123 esac
 124 case ${targets[0]} in
 125   kw|kww)
 126     prospective_mps=(/a)
 127     ;;
 128 esac
 129
 130 for mp in ${prospective_mps[@]}; do # default mountpoints to sync
 131   if [[ -e /nocow/btrfs-stale/$mp ]]; then
 132     echo "$0: warning: $mp stale, not adding to default mountpoints"
 133     continue
 134   fi
 135   if awk '{print $2}' /etc/fstab | grep -xF $mp &>/dev/null; then
 136     mountpoints+=($mp)
 137   fi
 138 done
 139
 140 echo "mountpoints: ${mountpoints[*]}"
 141
 142 ##### end command line parsing ########
 143
 144 rsync-dirs() {
 145   local host=$1
 146   local path=$2
 147   m rsync $dry_run_arg -ahi --relative --delete "$path" "root@$host:/"
 148 }
 149
 150 vol-conf() {
 151   cat >>/etc/btrbk.conf <<EOF
 152 volume $vol
 153 EOF
 154 }
 155 sub-conf() {
 156   cat >>/etc/btrbk.conf <<EOF
 157 subvolume $sub
 158 EOF
 159 }
 160 tg-conf() {
 161   cat >>/etc/btrbk.conf <<EOF
 162 target send-receive ssh://$tg$vol/btrbk
 163 EOF
 164 }
 165 m() { printf "%s: %s\n" "${0##*/}" "$*";  "$@"; }
 166
 167
 168 if ! which btrbk &>/dev/null; then
 169   echo "$0: error: no btrbk binary found"
 170   exit 1
 171 fi
 172 # if our mountpoints are from stale snapshots,
 173 # it doesn't make sense to do a backup.
 174 check-subvol-stale ${mountpoints[@]} || exit 1
 175
 176
 177 cat >/etc/btrbk.conf <<EOF
 178 ssh_identity /root/.ssh/home
 179 # Just a guess that local7 is a good facility to pick.
 180 # It's a bit odd that the transaction log has to be logged to
 181 # a file or syslog, while other output is sent to std out.
 182 # The man does not mention a way for them to be together, but
 183 # I dunno if setting a log level like warn might also output
 184 # transaction info.
 185 transaction_syslog local7
 186
 187 # 20%ish speedup[]
 188 stream_buffer 512m
 189
 190 # so we only run one at a time
 191 lockfile                   /var/lock/btrbk.lock
 192
 193 # default format of short does not accomidate hourly preservation setting
 194 timestamp_format long-iso
 195
 196 # only make a snapshot if things have changed
 197 snapshot_create onchange
 198 # I could make this different from target_preserve,
 199 # if one disk had less space.
 200 # for now, keeping them equal.
 201 snapshot_preserve 36h 14d 8w 24m
 202 snapshot_preserve_min 4h
 203 snapshot_dir btrbk
 204
 205 # so, total backups = ~89
 206 target_preserve 36h 14d 8w 24m
 207 target_preserve_min 4h
 208
 209 # if something fails and it's not obvious, try doing
 210 # btrbk -l debug -v dryrun
 211
 212 rate_limit $rate_limit
 213 EOF
 214
 215
 216
 217 for tg in ${targets[@]}; do
 218   # for an initial run, btrbk requires the dir to exist.
 219   # also use this opportunity to kill emacs, because it doesn't
 220   # notice that the file has changed out from underneath it
 221   ssh root@$tg mkdir -p /mnt/root/btrbk
 222 done
 223
 224
 225 for m in ${mountpoints[@]}; do
 226   # for /i, some special cases. there is just one static target and direction.
 227   if [[ $m == /i ]]; then
 228     vol=/mnt/iroot
 229     vol-conf
 230     sub=i
 231     sub-conf
 232     tg=frodo
 233     vol=/mnt/root
 234     tg-conf
 235   else
 236     vol=/mnt/root
 237     vol-conf
 238     sub=${m##*/}
 239     sub-conf
 240     for tg in ${targets[@]}; do
 241       tg-conf
 242     done
 243   fi
 244 done
 245
 246
 247 # todo: umount first to ensure we don't have any errors
 248 # todo: do some kill fuser stuff to make umount more reliable
 249
 250
 251 if $conf_only; then
 252   exit
 253 fi
 254
 255 if $dry_run; then
 256   m btrbk -v -n $resume_arg run
 257 else
 258   # -q and just using the syslog option seemed nice,
 259   # but it doesn't show when a send has a parent and when it doesn't.
 260   m btrbk $verbose_arg $progress_arg $resume_arg run
 261 fi
 262
 263 # if we have it, sync to systems which don't
 264 if mountpoint $rsync_mountpoint >/dev/null; then
 265   for tg in ${targets[@]}; do
 266     case $tg in
 267       tp|li|lk)
 268         for x in /p/c/machine_specific/*.hosts; do
 269           if grep -qxF $tg $x; then
 270             dir=${x%.hosts}
 271             rsync-dirs $tg $dir
 272           fi
 273         done
 274         ;;
 275     esac
 276   done
 277 fi
 278
 279 if ! $dry_run; then
 280   m $script_dir/mount-latest-remote ${targets[@]}
 281 fi
 282
 283
 284 # todo: move variable data we don't care about backing up
 285 # to /nocow and symlink it.
 286
 287
 288 # background on btrbk timezones. with short/long, timestamps use local time.
 289 # for long, if your local time moves backwards, by moving timezones or
 290 # for an hour when daylight savings changes it, you will temporarily get
 291 # a more aggressive retention policy for the overlapping period, and
 292 # vice versa for the opposite timezone move. The alternative is using
 293 # long-iso, which puts timezone info into the timestamp, which means
 294 # that instead of shifting time, you shift the start of day/week/month
 295 # which is used for retention to your new local time, which means for
 296 # example, if you moved forward by 8 hours, the daily/weekly/monthly
 297 # retention will be 8 hours more aggressive since midnight is at a new
 298 # time, unless you fake the timzeone using the TZ env variable.
 299 # However, in the short term, there will be no inconsistencies.
 300 # I don't see any problem with shifting when the day starts for
 301 # retention, so I'm using long-iso.
 302
 303 # note to create a long-iso timestamp: date +%Y%m%dT%H%M%S%z