@Override
  public void cleanupResource() {
    disconnect();
  }
Return the ObjectName for the SystemMemberMBean representing the specified distributed member
or null if the member is not found.

@param distributedMember the distributed member to manage
@return the ObjectName for the SystemMemberMBean
geode-core/src/main/java/org/apache/geode/admin/jmx/internal/AdminDistributedSystemJmxImpl.java