show a warning if the sequence id was not fetched

plugins/localdump/couchdb2.sh

@@ -21,6 +21,7 @@
 # 2022-04-14         v1.6  backup security infos (no restore yet)
 # 2022-04-21         v1.7  restore security infos
 # 2022-10-07  ah     v1.8  unescape regex with space to prevent "grep: warning: stray \ before white space"
+# 2023-06-06  ah     v1.9  show a warning if the sequence id was not fetched
 # ================================================================================
 
 if [ -z "$BACKUP_TARGETDIR" ]; then
@@ -218,7 +219,11 @@ function _doBackupOfSingleInstance(){
       )
       
     else
-      echo
+      if [ -z "$sSequenceCurrent" ]; then
+        echo "WARNING: unable to fetch current sequence ID - maybe the dump will fail."
+      else
+        echo
+      fi
       echo "update_seq --+-- current [${sSequenceCurrent}]" 
       echo "             +-- backup  [${sSequenceLast}]"
       echo -n "Need to backup ... "