Implement snapshot replication.

Author: FransUrbo

src/zfs-auto-snapshot.8

@@ -46,11 +46,17 @@ PRE is 'zfs\-auto\-snap' by default.
 \fB\-q\fR, \fB\-\-quiet\fR
 Suppress warnings and notices at the console.
 .TP
-\fB\-\-send\-full\fR=\fIF\fR
-Send zfs full backup. Unimplemented.
+\fB\-\-send\-full\fR=\fIhost|ip address\fR
+Send zfs full backup to \fIhost\fR (or \fIip address\fR).
 .TP
-\fB\-\-send\-incr\fR=\fIF\fR
-Send zfs incremental backup. Unimplemented.
+\fB\-\-send\-incr\fR=\fIhost\fR
+Send zfs incremental backup to \fIhost\fR (or \fIip address\fR).
+.TP
+\fB\-\-send\-opts\fR=\fIOPTS\fR
+Option(s) passed to 'zfs send'.
+.TP
+\fB\-\-recv\-opts\fR=\fIOPTS\fR
+Option(s) passed to 'zfs receive'.
 .TP
 \fB\-\-sep\fR=\fICHAR\fR
 Use CHAR to separate date stamps in snapshot names.

src/zfs-auto-snapshot.sh

@@ -34,6 +34,11 @@ opt_keep=''
 opt_label=''
 opt_prefix='zfs-auto-snap'
 opt_recursive=''
+opt_send_type=''
+opt_send_host=''
+opt_recv_pool=''
+opt_send_opts=''
+opt_recv_opts=''
 opt_sep='_'
 opt_setauto=''
 opt_syslog=''
@@ -68,6 +73,8 @@ print_usage ()
   -q, --quiet        Suppress warnings and notices at the console.
       --send-full=F  Send zfs full backup. Unimplemented.
       --send-incr=F  Send zfs incremental backup. Unimplemented.
+      --send-opts=F  Option(s) passed to 'zfs send'.
+      --recv-opts=F  Option(s) passed to 'zfs receive'.
       --sep=CHAR     Use CHAR to separate date stamps in snapshot names.
   -g, --syslog       Write messages into the system log.
   -r, --recursive    Snapshot named filesystem and all descendants.
@@ -159,6 +166,8 @@ do_snapshots () # properties, flags, snapname, oldglob, [targets...]
 	# global WARNING_COUNT
 	# global SNAPSHOTS_OLD
 
+	SNAPS_DONE=''
+
 	for ii in $TARGETS
 	do
 		if [ -n "$opt_do_snapshots" ]
@@ -170,6 +179,8 @@ do_snapshots () # properties, flags, snapname, oldglob, [targets...]
 			if [ $RUNSNAP -eq 1 ] && do_run "zfs snapshot $PROPS $FLAGS '$ii@$NAME'"
 			then
 				[ "$opt_post_snapshot" != "" ] && do_run "$opt_post_snapshot $ii $NAME"
+				[ -n "$opt_send_host" ] && SNAPS_DONE="$SNAPS_DONE
+$ii@$NAME"
 				SNAPSHOT_COUNT=$(( $SNAPSHOT_COUNT + 1 ))
 			else
 				WARNING_COUNT=$(( $WARNING_COUNT + 1 ))
@@ -203,6 +214,78 @@ do_snapshots () # properties, flags, snapname, oldglob, [targets...]
 	done
 }
 
+do_send () # snapname, oldglob
+{
+	local NAME="$1"
+	local GLOB="$2"
+	local ii
+	local remote="ssh $opt_send_host zfs receive $opt_recv_opts $opt_recv_pool"
+
+	# STEP 1: Go throug all snapshots we've created
+	for ii in $SNAPS_DONE
+	do
+		opts=''
+		SNAPS_SEND=''
+
+		dset=${ii%@*}
+
+		# STEP 2: Go through ALL snapshots that exist, look for exact
+		#         match on dataset/volume (with snapshot matching 'GLOB').
+		for jj in $SNAPSHOTS_OLD
+		do
+			# Check whether this is an old snapshot of the filesystem.
+			if [ -z "${jj#$dset@$GLOB}" ]; then
+				# We want the FIRST one (which is the last in time
+				# before the one we just created in do_snapshot()).
+				# Also, here we just need the snapshot name.
+				last_snap="${jj#*@}"
+				break
+			fi
+		done
+
+		# NOTE: If we don't have any previous snapshots (for example, we've
+		#       just created the first one) we can end up with last_snap=''
+		#       here.
+		#       If we're called with '--send-incr' we have to options:
+		#         1: We change from incremental to full.
+		#         2: We accept that the user have said INCR, and stick with
+		#            it.
+		if [ "$opt_send_type" = "incr" -a -z "$last_snap" ]; then
+			if [ -n "$opt_verbose" ]; then
+				echo "WARNING: No previous snapshots exist but we where called"
+				echo "         with --send-incr. Can not continue."
+				echo "         Please rerun with --send-full."
+			fi
+			return 1
+		fi
+
+		if [ -n "$opt_recursive" -a -n "$last_snap" ]; then
+			# STEP 3: Again, go through ALL snapshots that exists, but this
+			#         time only look for the snapshots that 'starts with'
+			#         the dataset/volume in question AND 'ends with'
+			#         the exact snapshot name/date in step 2.
+			for jj in $SNAPSHOTS_OLD
+			do
+				if echo "$jj" | grep -qE "^$dset.*@$last_snap"; then
+					SNAPS_SEND="$SNAPS_SEND
+$jj"
+				fi
+			done
+		else
+			SNAPS_SEND="$ii"
+		fi
+
+		# STEP 4: Go through all snapshots that is to be transfered and send them.
+		for jj in $SNAPS_SEND
+		do
+			if [ "$opt_send_type" = "incr" ]; then
+				do_run "zfs send $opt_send_opts -i $jj $ii | $remote"
+			else
+				do_run "zfs send $opt_send_opts -R $jj | $remote"
+			fi
+		done
+	done
+}
 
 # main ()
 # {
@@ -212,6 +295,7 @@ GETOPT=$(getopt \
   --longoptions=event:,keep:,label:,prefix:,sep: \
   --longoptions=debug,help,quiet,syslog,verbose \
   --longoptions=pre-snapshot:,post-snapshot:,destroy-only \
+  --longoptions=send-full:,send-incr:,send-opts:,recv-opts: \
   --options=dnshe:l:k:p:rs:qgv \
   -- "$@" ) \
   || exit 128
@@ -296,6 +380,30 @@ do
 			opt_recursive='1'
 			shift 1
 			;;
+		(--send-full)
+			opt_send_type='full'
+
+			opt_send_host=$(echo "$2" | sed 's,:.*,,')
+			opt_recv_pool=$(echo "$2" | sed 's,.*:,,')
+
+			opt_send_opts="$opt_send_opts -R"
+			shift 2
+			;;
+		(--send-incr)
+			opt_send_type='incr'
+
+			opt_send_host=$(echo "$2" | sed 's,:.*,,')
+			opt_recv_pool=$(echo "$2" | sed 's,.*:,,')
+			shift 2
+			;;
+		(--send-opts)
+			opt_send_opts="$2"
+			shift 2
+			;;
+		(--recv-opts)
+			opt_recv_opts="$2"
+			shift 2
+			;;
 		(--sep)
 			case "$2" in 
 				([[:alnum:]_.:\ -])
@@ -567,6 +675,8 @@ test -n "$opt_dry_run" \
 do_snapshots "$SNAPPROP" ""   "$SNAPNAME" "$SNAPGLOB" "$TARGETS_REGULAR"
 do_snapshots "$SNAPPROP" "-r" "$SNAPNAME" "$SNAPGLOB" "$TARGETS_RECURSIVE"
 
+do_send "$SNAPNAME" "$SNAPGLOB"
+
 print_log notice "@$SNAPNAME," \
   "$SNAPSHOT_COUNT created," \
   "$DESTRUCTION_COUNT destroyed," \