commit 3e456fa85df5f10d76b6a32ba300cf4e945ff3c4 Author: nachoparker Date: Fri Mar 9 14:31:45 2018 +0100 Initial commit diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..94a9ed0 --- /dev/null +++ b/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/README.md b/README.md new file mode 100644 index 0000000..d37c1b3 --- /dev/null +++ b/README.md @@ -0,0 +1,110 @@ +# btrfs-sync + +Smart and easy sync of BTRFS snapshots, locally or through SSH. + +![Example](resources/btrfs-sync.gif) + +Can be used in conjunction with [btrfs-snp](https://ownyourbits.com/2017/12/27/schedule-btrfs-snapshots-with-btrfs-snp/) + +``` +# btrfs-sync --verbose --delete /home/user/.snapshots user@server:/media/USBdrive/home-snapshots +* Skip existing '/home/user/.snapshots/monthly_2018-01-09_200102' +* Skip existing '/home/user/.snapshots/monthly_2018-02-08_200102' +* Skip existing '/home/user/.snapshots/weekly_2018-02-09_140102' +* Skip existing '/home/user/.snapshots/weekly_2018-02-16_150102' +* Skip existing '/home/user/.snapshots/weekly_2018-02-23_150102' +* Skip existing '/home/user/.snapshots/weekly_2018-03-02_180102' +* Skip existing '/home/user/.snapshots/daily_2018-03-03_000101' +* Skip existing '/home/user/.snapshots/daily_2018-03-04_080101' +* Skip existing '/home/user/.snapshots/daily_2018-03-05_100102' +* Skip existing '/home/user/.snapshots/daily_2018-03-06_100102' +* Skip existing '/home/user/.snapshots/daily_2018-03-07_110102' +* Synchronizing '/home/user/.snapshots/hourly_2018-03-08_090101' using seed '.snapshots/hourly_2018-03-07_090101'... +time elapsed [0:00:24] | rate [11.1MiB/s] | total size [ 132MiB] +* Synchronizing '/home/user/.snapshots/hourly_2018-03-08_100101' using seed '.snapshots/hourly_2018-03-09_090101'... +time elapsed [0:01:05] | rate [11.1MiB/s] | total size [ 275MiB] +* Deleting non existent snapshots... +Delete subvolume (no-commit): '/media/USBdrive/home-snapshots/hourly_2018-03-08_090101' +Delete subvolume (no-commit): '/media/USBdrive/home-snapshots/hourly_2018-03-08_100101' +``` + +## Features + +- Simple syntax +- Progress indication +- Support for _xz_ or _pbzip2_ compression in order to save bandwidth. +- Retention policy +- Automatic incremental synchronization +- Cron friendly + +## Usage + +The syntax is similar to that of _scp_ + +``` +Usage: + btrfs-sync [options] [...] [[user@]host:] + + -k|--keep NUM keep only last sync'ed snapshots + -d|--delete delete snapshots in that don't exist in + -z|--xz use xz compression. Saves bandwidth, but uses one CPU + -Z|--pbzip2 use pbzip2 compression. Saves bandwidth, but uses all CPUs + -q|--quiet don't display progress + -v|--verbose display more information + -h|--help show usage + + can either be a single snapshot, or a folder containing snapshots + requires privileged permissions at for the 'btrfs' command +``` + +## Examples + +### Manual + +Synchronize snapshots of _home_ to a USB drive + +``` +# btrfs-sync /home/user/.snapshots /media/USBdrive/home-snapshots +``` + +Synchronize snapshots of _home_ to a USB drive in another machine + +``` +# btrfs-sync /home/user/.snapshots user@server:/media/USBdrive/home-snapshots +``` + +Synchronize one snapshot of _home_ to a USB drive in another machine + +``` +# btrfs-sync /home/user/.snapshots/monthly_2018-02-08_200102 user@server:/media/USBdrive/home-snapshots +``` + +Synchronize only monthly snapshots of _home_ to a USB drive in another machine + +``` +# btrfs-sync /home/user/.snapshots/monthly_* user@server:/media/USBdrive/home-snapshots +``` + +### Cron + +Daily synchronization over the internet, keep only last 50 + +``` +cat > /etc/cron.daily/btrfs-sync < /etc/cron.daily/btrfs-sync < [...] [[user@]host:] +# +# -k|--keep NUM keep only last sync'ed snapshots +# -d|--delete delete snapshots in that don't exist in +# -z|--xz use xz compression. Saves bandwidth, but uses one CPU +# -Z|--pbzip2 use pbzip2 compression. Saves bandwidth, but uses all CPUs +# -q|--quiet don't display progress +# -v|--verbose display more information +# -h|--help show usage +# +# can either be a single snapshot, or a folder containing snapshots +# requires privileged permissions at for the 'btrfs' command +# +# Cron example: daily synchronization over the internet, keep only last 50 +# +# cat > /etc/cron.daily/btrfs-sync < +# GPL licensed (see end of file) * Use at your own risk! +# +# More at https://ownyourbits.com +# + +# help +print_usage() { + echo "Usage: + $BIN [options] [...] [[user@]host:] + + -k|--keep NUM keep only last sync'ed snapshots + -d|--delete delete snapshots in that don't exist in + -z|--xz use xz compression. Saves bandwidth, but uses one CPU + -Z|--pbzip2 use pbzip2 compression. Saves bandwidth, but uses all CPUs + -q|--quiet don't display progress + -v|--verbose display more information + -h|--help show usage + + can either be a single snapshot, or a folder containing snapshots + requires privileged permissions at for the 'btrfs' command + +Cron example: daily synchronization over the internet, keep only last 50 + +cat > /etc/cron.daily/btrfs-sync </dev/null ) +[[ $? -ne 0 ]] && { echo "error parsing arguments"; exit 1; } +eval set -- "$OPTS" + +while true; do + case "$1" in + -h|--help ) print_usage; exit 0 ;; + -q|--quiet ) QUIET=1 ; shift 1 ;; + -d|--delete ) DELETE=1 ; shift 1 ;; + -k|--keep ) KEEP=$2 ; shift 2 ;; + -z|--xz ) ZIP=xz PIZ=( xz -d ); shift 1 ;; + -Z|--pbzip2 ) ZIP=pbzip2 PIZ=( pbzip2 -d ); shift 1 ;; + -v|--verbose) SILENT="" VERBOSE=1 ; shift 1 ;; + --) shift; break ;; + esac +done + +SRC=( "${@:1:$#-1}" ) +DST="${@: -1}" + +# detect remote dst argument +[[ "$DST" =~ : ]] && { + NET="$( sed 's|:.*||' <<<"$DST" )" + DST="$( sed 's|.*:||' <<<"$DST" )" + SSH=( ssh -o ServerAliveInterval=5 -o ConnectTimeout=1 "$NET" ) +} +[[ "$SSH" != "" ]] && DST_CMD=( ${SSH[@]} ) || DST_CMD=( eval ) + +#---------------------------------------------------------------------------------------------------------- + +# checks + +## general checks +[[ $# -lt 2 ]] && { print_usage ; exit 1; } +[[ ${EUID} -ne 0 ]] && { echo "Must be run as root. Try 'sudo $BIN'"; exit 1; } +${DST_CMD[@]} true &>/dev/null || { echo "SSH access error to $NET" ; exit 1; } + +## src checks +for s in "${SRC[@]}"; do + src="$(cd "$s" &>/dev/null && pwd)" || { echo "$s not found"; exit 1; } #abspath + btrfs subvolume show "$src" &>/dev/null && SRCS+=( "$src" ) || \ + for dir in $( ls -drt "$src"/* 2>/dev/null ); do + btrfs subvolume show "$dir" &>/dev/null && SRCS+=( "$dir" ) + done +done +[[ ${#SRCS[@]} -eq 0 ]] && { echo "no BTRFS subvolumes found"; exit 1; } + +## check pbzip2 +[[ "$ZIP" == "pbzip2" ]] && { + type pbzip2 &>/dev/null && \ + "${DST_CMD[@]}" type pbzip2 &>/dev/null || { + echo "INFO: 'pbzip2' not installed on both ends, fallback to 'xz'" + ZIP=xz PIZ=unxz + } +} + +## use 'pv' command if available +PV=( pv -F"time elapsed [%t] | rate %r | total size [%b]" ) +[[ "$QUIET" == "1" ]] && PV=( cat ) || type pv &>/dev/null || { + echo "INFO: install the 'pv' package in order to get a progress indicator" + PV=( cat ) +} + +#---------------------------------------------------------------------------------------------------------- + +# sync snapshots + +## get dst snapshots ( DSTS, DST_UUIDS ) +get_dst_snapshots() { + local DST="$1" + unset DSTS DST_UUIDS + while read entry; do + DST_UUIDS+=( "$( sed 's=|.*==' <<<"$entry" )" ) + DSTS+=( "$( sed 's=.*|==' <<<"$entry" )" ) + done < <( + "${DST_CMD[@]}" " + DSTS=( \$( ls -d \"$DST\"/* 2>/dev/null ) ) + for dst in \${DSTS[@]}; do + UUID=\$( sudo btrfs su sh \"\$dst\" 2>/dev/null | grep 'Received UUID' | awk '{ print \$3 }' ) + [[ \"\$UUID\" == \"-\" ]] || [[ \"\$UUID\" == \"\" ]] && continue + echo \"\$UUID|\$dst\" + done" + ) +} + +## sync incrementally +sync_snapshot() { + local SRC="$1" + local ID LIST PATH_ DATE SECS SEEDS SEED SEED_PATH SEED_ARG + + # detect existing + SRC_UUID=$( btrfs su sh "$SRC" | grep "UUID:" | head -1 | awk '{ print $2 }' ) + for id in "${DST_UUIDS[@]}"; do + [[ "$SRC_UUID" == "$id" ]] && { echov "* Skip existing '$SRC'"; return 0; } + done + + # try to get most recent src snapshot that exists in dst to use as a seed + LIST="$( btrfs subvolume list -su "$SRC" )" + for id in "${DST_UUIDS[@]}"; do + ID=$(btrfs su sh -u "$id" "$SRC" 2>/dev/null|grep "UUID:"|head -1|awk '{print $2}') + PATH_=$( awk "{ if ( \$14 == \"$ID\" ) print \$16 }" <<<"$LIST" ) + DATE=$( awk "{ if ( \$14 == \"$ID\" ) print \$11, \$12 }" <<<"$LIST" ) + + [[ "$ID" == "" ]] || [[ "$PATH_" == "$( basename "$SRC" )" ]] && continue + + SECS=$( date -d "$DATE" +"%s" ) + SEEDS+=( "$SECS|$PATH_" ) + done + SEED="$(for s in "${SEEDS[@]}";do echo "$s";done|sort -V|tail -1|cut -f2 -d'|')" + + # incremental sync argument + [[ "$SEED" != "" ]] && { + SEED_PATH="$( dirname "$SRC" )/$( basename $SEED )" + [[ -d "$SEED_PATH" ]] && + SEED_ARG=( -p "$SEED_PATH" ) || \ + echo "INFO: couldn't find $SEED_PATH. Non-incremental mode" + } + + # do it + echo -n "* Synchronizing '$src'" + [[ "$SEED_ARG" != "" ]] && echov -n " using seed '$SEED'" + echo "..." + + { btrfs send -q ${SEED_ARG[@]} "$SRC" \ + | "$ZIP" \ + | "${PV[@]}" \ + | "${DST_CMD[@]}" "${PIZ[@]} | sudo btrfs receive \"$DST\" 2>&1 | grep -v '^At subvol '" \ + || exit 1; } | grep -v "^At snapshot " + get_dst_snapshots "$DST" # sets DSTS DST_UUIDS +} + +#---------------------------------------------------------------------------------------------------------- + +# sync all snapshots found in src +get_dst_snapshots "$DST" # sets DSTS DST_UUIDS +for src in "${SRCS[@]}"; do + sync_snapshot "$src" +done + +#---------------------------------------------------------------------------------------------------------- + +# retention policy +[[ "$KEEP" != 0 ]] && \ + [[ ${#DSTS[@]} -gt $KEEP ]] && \ + echov "* Pruning old snapshots..." && \ + for (( i=0; i < $(( ${#DSTS[@]} - KEEP )); i++ )); do + PRUNE_LIST+=( "${DSTS[$i]}" ) + done && \ + ${DST_CMD[@]} sudo btrfs subvolume delete "${PRUNE_LIST[@]}" $SILENT + +# delete flag +[[ "$DELETE" == 1 ]] && \ + for dst in "${DSTS[@]}"; do + FOUND=0 + for src in "${SRCS[@]}"; do + [[ "$( basename $src )" == "$( basename $dst )" ]] && { FOUND=1; break; } + done + [[ "$FOUND" == 0 ]] && DEL_LIST+=( "$dst" ) + done +[[ "$DEL_LIST" != "" ]] && \ + echov "* Deleting non existent snapshots..." && \ + ${DST_CMD[@]} sudo btrfs subvolume delete "${DEL_LIST[@]}" $SILENT + +# License +# +# This script is free software; you can redistribute it and/or modify it +# under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This script is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this script; if not, write to the +# Free Software Foundation, Inc., 59 Temple Place, Suite 330, diff --git a/resources/btrfs-sync.gif b/resources/btrfs-sync.gif new file mode 100644 index 0000000..f3f9fa4 Binary files /dev/null and b/resources/btrfs-sync.gif differ