@Override
    public void preCreateTableAction(final ObserverContext<MasterCoprocessorEnvironment> ctx,
      final TableDescriptor desc, final RegionInfo[] regions) throws IOException {

      if (desc.getTableName().equals(TABLE)) {
        throw new AccessDeniedException("Don't allow creation of table");
      }
    }
Check if CompletedProcedureCleaner cleans up failed nonce procedures.
hbase-server/src/test/java/org/apache/hadoop/hbase/procedure/TestFailedProcCleanup.java