private boolean shouldBootstrapDumpExternalTable(String tableName) {
    // Note: If repl policy is replaced, then need to dump external tables if table is getting replicated
    // for the first time in current dump. So, need to check if table is included in old policy.
    return conf.getBoolVar(HiveConf.ConfVars.REPL_INCLUDE_EXTERNAL_TABLES)
            && (conf.getBoolVar(HiveConf.ConfVars.REPL_BOOTSTRAP_EXTERNAL_TABLES)
            || !ReplUtils.tableIncludedInReplScope(work.oldReplScope, tableName));
  }
Decide whether to dump external tables.
@param tableName - Name of external table to be replicated
@return true if need to bootstrap dump external table and false if not.
ql/src/java/org/apache/hadoop/hive/ql/exec/repl/ReplDumpTask.java