White Papers

5 No Restrictions | Filter Dialects |
1 Introduction
PowerEdge servers and chassis for modular servers, include management controllers, iDRAC and CMC
(Chassis Management Controller). These controllers assist the system administrators to manage and
monitor the chassis and servers. The management controllers provide functionality of management
through GUI, CLI, and programmatic (WS-Man) interfaces.
The WS-Man interface is a DMTF (Distributed Management Task Force) specification for systems
management through Web Services architecture. WS-Man interface can be used to manage the server
through a series of Simple Object Access Protocol (SOAP) encapsulated Web-Based Enterprise
Management (WBEM) commands. Enumeration is used to inventory the devices under management and
Invoke is used to change the states and configurations of a managed entity.
The size of WS-Man enumeration data file can be large. If spanning across large structures of managed
entities, filter dialects are provided to find out certain instances or data that are necessary to the consumer.
This whitepaper describes the techniques to filter data from the WS-Man enumeration. The use of filters
varies between GET commands. GET command returns a single instance defined by key-binding values
(unique identifiers). However, using a filter can return multiple instances of each, matching the entered
condition.
2 WS-Man Filters
WS-Man enumeration on a class returns all the instances of that particular class. If a class has children
(derived) classes, enumeration on the parent, returns instances of all the children. The return data can be
of large size and hence difficult to manage. The filters enable the client to select the necessary instances.
The following filters are supported in the WS-Man stack provided by Dell:
a) Selectors
b) CIM Query Language (CQL) and Windows Management Instrumentation Query Language (WQL)
c) Association Filters
Note: XPATH filters are not supported in Dell WS-Man stack
2.1 Usage of Filter
A basic example of a filter from the Microsoft-provided WinRM application is given here.