- # 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.
- # Otherwise, perform a full replicate.
- grep -q ${previous_backup_marker} $remote_list
- full=$?
- grep -q ${previous_backup_marker} $local_list
- full=$(($full || $?))
-
- if [[ $full == 0 ]]; then
- ssh $remote $zfs send -R -I${previous_backup_marker} ${current_backup_marker} |
- $zfs receive -vF -d ${local_pool}/${remote_fs%/*}
- if [[ $? != 0 ]]; then
- echo "-E- remote incremental $zfs send command failed"
- exit 1
- fi
- else
- ssh $remote $zfs send -R ${current_backup_marker} |
- $zfs receive -vF -d ${local_pool}/${remote_fs%/*}
- if [[ $? != 0 ]]; then
- echo "-E- remote full $zfs send command failed"
- exit 1
- fi
- fi
-
- # destroy the previous backup markers now that we've replicated past them
- $zfs destroy ${local_pool}/${previous_backup_marker} > /dev/null 2>&1
- ssh $remote $zfs destroy ${previous_backup_marker} > /dev/null 2>&1
-
- # Rename the current backup marker to be the previous backup marker
- $zfs rename ${local_pool}/${current_backup_marker} ${local_pool}/${previous_backup_marker}
- if [[ $? != 0 ]]; then
- echo "-E- local $zfs rename command failed"
+# Create the current backup marker snapshot on the remote system
+ssh $remote $zfs snapshot ${current_backup_marker}
+if [ $? != 0 ]; then
+ echo "-E- remote $zfs snapshot command failed"
+ exit 1
+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
+ echo "-E- remote incremental $zfs rollback command failed"