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 usage() {
  21     echo "top of script file:"
  22     sed -n '1,/^[# ]*end command line/{p;b};q' "$0"
  23     exit $1
  24 }
  25
  26 script_dir=$(dirname $(readlink -f "$BASH_SOURCE"))
  27
  28 # todo: finish figuring out fai / distro-setup
  29 # initial fstab / subvol setup.
  30
  31 conf_only=false
  32 dry_run=false # mostly for testing
  33 resume_arg=
  34
  35 temp=$(getopt -l help hcnrt: "$@") || usage 1
  36 eval set -- "$temp"
  37 while true; do
  38     case $1 in
  39         -c) conf_only=true; shift ;;
  40         -n) dry_run=true; dry_run_arg=-n; shift ;;
  41         -r) resume_arg=-r; shift ;;
  42         -t) IFS=, targets=($2); shift 2 ;;
  43         -h|--help) usage ;;
  44         --) shift; break ;;
  45         *) echo "$0: Internal error!" ; exit 1 ;;
  46     esac
  47 done
  48 read primary <<<"$@"
  49
  50 ##### end command line parsing ########
  51
  52 rsync-dirs() {
  53     local host=$1
  54     local path=$2
  55     rsync $dry_run_arg -ahi --relative --delete "$path" "root@$host:/"
  56 }
  57
  58 vol-conf() {
  59     cat >>/etc/btrbk.conf <<EOF
  60 volume $vol
  61 EOF
  62 }
  63 sub-conf() {
  64     cat >>/etc/btrbk.conf <<EOF
  65 subvolume $sub
  66 EOF
  67 }
  68 tg-conf() {
  69     cat >>/etc/btrbk.conf <<EOF
  70 target send-receive ssh://$tg$vol/btrbk
  71 EOF
  72 }
  73
  74
  75
  76 if ! which btrbk &>/dev/null; then
  77     echo "$0: error: no btrbk binary found"
  78 fi
  79
  80 cat >/etc/btrbk.conf <<'EOF'
  81 ssh_identity /root/.ssh/id_rsa
  82
  83 # so we only run one at a time
  84 lockfile                   /var/lock/btrbk.lock
  85
  86 # default format of short does not accomidate hourly preservation setting
  87 timestamp_format long-iso
  88
  89 # only make a snapshot if things have changed
  90 snapshot_create onchange
  91 # much less snapshots because I have less space on the
  92 # local filesystem.
  93 #snapshot_preserve 2h 2d
  94 # for now, keeping them equal for simplicity sake
  95 snapshot_preserve 48h 14d 8w 24m
  96 snapshot_preserve_min 6h
  97 snapshot_dir btrbk
  98
  99 # so, total backups = ~89
 100 target_preserve 48h 14d 8w 24m
 101 target_preserve_min 6h
 102
 103 # if something fails and it's not obvious, try doing
 104 # btrbk -l debug -v dryrun
 105 EOF
 106
 107 # note q is owned by root:1000
 108 # note p is owned 1000:1000 and chmod 700
 109 mountpoints=(/q)
 110 if awk '{print $2}' /etc/fstab | grep -xF /p &>/dev/null; then
 111     mountpoints+=(/p)
 112 fi
 113
 114 # if our mountpoints are from stale snapshots,
 115 # it doesn't make sense to do a backup.
 116 check-subvol-stale ${mountpoints[@]} || exit 1
 117
 118 if [[ ! $targets ]]; then
 119     case $HOSTNAME in
 120         tp|x2)
 121             if ! timeout -s 9 10 ssh frodo :; then
 122                 targets=($HOME_DOMAIN)
 123             fi
 124             ;;
 125     esac
 126     targets=(frodo)
 127 fi
 128
 129
 130 # for i, we just do a 1 way sync from master to backup,
 131 # and manually manage any changes to that.
 132 do_i=false
 133 for tg in ${targets[@]}; do
 134     # for an initial run, btrbk requires the dir to exist
 135     ssh root@$tg mkdir -p /mnt/root/btrbk
 136     if [[ $tg == frodo && $HOSTNAME == treetowl ]]; then
 137         do_i=true
 138     fi
 139 done
 140
 141
 142 vol=/mnt/root
 143 vol-conf
 144 for m in ${mountpoints[@]}; do
 145     sub=${m##*/}
 146     sub-conf
 147     for tg in ${targets[@]}; do
 148         tg-conf
 149     done
 150 done
 151
 152 if $do_i; then
 153     vol=/mnt/iroot
 154     vol-conf
 155     sub=i
 156     sub-conf
 157     tg=frodo
 158     vol=/mnt/root
 159     tg-conf
 160 fi
 161
 162
 163
 164 # todo: umount first to ensure we don't have any errors
 165 # todo: do some kill fuser stuff to make umount more reliable
 166 # todo: run this on a systemd timer on $primary, once per hour,
 167 # and if primary is, change that timer over to primary, and make
 168 # sure we mount the latest
 169
 170
 171
 172 if $conf_only; then
 173     exit
 174 fi
 175
 176 if $dry_run; then
 177     btrbk -n $resume_arg run
 178 else
 179     # -q and just using the syslog option seemed nice,
 180     # but it doesn't show when a send has a parent and when it doesn't.
 181     btrbk $resume_arg run
 182 fi
 183
 184 # if we have /p, rsync to targets without /p
 185 if mountpoint /p >/dev/null; then
 186     for tg in ${targets[@]}; do
 187         case $tg in
 188             tp|li|lk)
 189                 for x in /p/c/machine_specific/*.hosts; do
 190                     if grep -qxF $tg $x; then
 191                         dir=${x%.hosts}
 192                         rsync-dirs $tg $dir
 193                     fi
 194                 done
 195                 ;;
 196         esac
 197     done
 198 fi
 199
 200 if ! $dry_run; then
 201     $script_dir/mount-latest-remote ${targets[@]}
 202 fi
 203
 204
 205 # todo: move variable data we don't care about backing up
 206 # to /nocow and symlink it.
 207
 208
 209 # background on btrbk timezones. with short/long, timestamps use local time.
 210 # for long, if your local time moves backwards, by moving timezones or
 211 # for an hour when daylight savings changes it, you will temporarily get
 212 # a more aggressive retention policy for the overlapping period, and
 213 # vice versa for the opposite timezone move. The alternative is using
 214 # long-iso, which puts timezone info into the timestamp, which means
 215 # that instead of shifting time, you shift the start of day/week/month
 216 # which is used for retention to your new local time, which means for
 217 # example, if you moved forward by 8 hours, the daily/weekly/monthly
 218 # retention will be 8 hours more aggressive since midnight is at a new
 219 # time, unless you fake the timzeone using the TZ env variable.
 220 # However, in the short term, there will be no inconsistencies.
 221 # I don't see any problem with shifting when the day starts for
 222 # retention, so I'm using long-iso.
 223
 224 # note to create a long-iso timestamp: date +%Y%m%dT%H%M%S%z