Added new destroy on full option

diff --git a/zfs-replicate b/zfs-replicate
index 57680fc637c4910e887c69d40c85279de229c07c..dc6dab215c592241685f6f90eb017ab4e6f85ded 100755 (executable)
--- a/zfs-replicate
+++ b/zfs-replicate
@@ -12,6 +12,10 @@ local_pool=backups
 # Set the email address to send notification to
 mailto=alan@pippins.net
 
+# When this variable is set, local filesystems will be destroyed 
+# before receiving a full streams into them from the remote source.
+destroy_local_filesystem_on_full_replicate=0
+
 # The ssh connection doesn't find zfs without this.
 zfs=/usr/sbin/zfs
 
@@ -94,9 +98,12 @@ if [ $? != 0 ]; then
 fi
 
 # List the snapshots on the local machine.
+# Don't list the current backup marker if it exists on the local side.
+# If you do, it can mess up the common finding algorithm below.
 local_list=$(mktemp /tmp/replicate.XXXXXX)
 $zfs list -H -t snapshot |
     grep ^${local_pool}/${remote_fs}@ |
+    grep -v ^${local_pool}/${current_backup_marker} | 
     awk "{gsub(/^$local_pool./,\"\",\$1); print\$1}" > $local_list
 if [ $? != 0 ]; then
   echo "-E- local $zfs list command failed"
@@ -176,9 +183,16 @@ else
     # Destroy the local filesystem if it exists before receving the full replicate
     zfs list ${local_pool}/${remote_fs} > /dev/null 2>&1
     if [ $? == 0 ]; then
-      zfs destroy -r ${local_pool}/${remote_fs}
-      if [ $? != 0 ]; then
-        echo "-E- remote full $zfs destroy command failed"
+      if [[ $destroy_local_filesystem_on_full_replicate == 1 ]]; then
+        $zfs destroy -r ${local_pool}/${remote_fs}
+        if [ $? != 0 ]; then
+          echo "-E- remote full $zfs destroy command failed"
+          exit 1
+        fi
+      else
+        echo "-W- We need to destroy a local filesystem before receiving a full stream."
+       echo "    However, since the option is set to prevent this, skipping replicate operation."
+        echo "$zfs destroy -r ${local_pool}/${remote_fs} not able to run" | /usr/bin/mailx -s "zfs-replicate-all unable to destroy local filesystem" $mailto
         exit 1
       fi
     fi