+ grep -v ^${local_pool}/${current_backup_marker} |
+ awk "{gsub(/^$local_pool./,\"\",\$1); print\$1}" > $local_list
+if [ $? != 0 ]; then
+ fatal_and_exit "-E- local $zfs list command failed" $mailto
+fi
+
+# Destroy the current backup marker snapshot on the remote system if it exists
+grep -q ${current_backup_marker} $remote_list
+if [ $? == 0 ]; then
+ ssh $remote $zfs destroy ${current_backup_marker}
+ if [ $? != 0 ]; then
+ fatal_and_exit "-E- remote $zfs destroy command failed" $mailto
+ fi
+fi
+
+# Create the current backup marker snapshot on the remote system
+ssh $remote $zfs snapshot ${current_backup_marker}
+if [ $? != 0 ]; then
+ fatal_and_exit "-E- remote $zfs snapshot command failed" $mailto
+fi
+
+# Check to see if the previous backup marker exists in the remote snapshot list.
+# Check to see if the previous backup marker exists in the local snapshot list.
+# If the previous backup markers exists, perform an incremental replicate. Else:
+# 1) check to see if a common snapshot exists, and perform an incremental replicate.
+# 2) if no common snapshot exists, destroy the local filesystem, and perform a full replicate.
+grep -q ${previous_backup_marker} $remote_list
+no_markers=$?
+grep -q ${previous_backup_marker} $local_list
+no_markers=$(($no_markers || $?))
+
+if [ $no_markers == 0 ]; then
+ # We found backup markers, incrementally send the new snaps
+
+ # First, rollback the local pool to the previous backup marker in case the previous
+ # backup was interrupted for some reason. If we don't do this, the zfs send -R command
+ # below may complain about snaps already existing as it tries to resend from the
+ # previous backup marker again from a previously interrupted replicate.
+ $zfs rollback -r ${local_pool}/${previous_backup_marker}
+ if [ $? != 0 ]; then
+ fatal_and_exit "-E- remote incremental $zfs rollback command failed" $mailto
+ fi
+ # Now it should be safe to send the snaps
+ if [[ $throttle_enable == 1 && -e $throttle ]]; then
+ ssh $remote $zfs send -R -I${previous_backup_marker} ${current_backup_marker} |
+ $throttle $throttle_opt | $zfs receive -vF -d ${local_pool}/${remote_pool}
+ else
+ ssh $remote $zfs send -R -I${previous_backup_marker} ${current_backup_marker} |
+ $zfs receive -vF -d ${local_pool}/${remote_pool}
+ fi
+ if [ $? != 0 ]; then
+ fatal_and_exit "-E- remote incremental $zfs send command failed" $mailto
+ fi
+else
+ # We didn't find any backup markers, next check to see if we have a common snapshot.
+
+ # See what the most recent snapshot on the remote end is.
+ latest=$(tail -n 1 $remote_list)