Ethernet CFM implementation for composite services
Composite service description
End-to-end test suite generation for composite services is available for VPLS and VLL Epipe services. In this context, a composite service is a set of services connected by one or more of the following:
Creating test suites and test policies for composite services is very similar to creating these for a regular service. Test generation options can be applied to modify the roles of managed and remote unmanaged up MEPs. See To configure an Ethernet CFM MD policy and subordinate objects . The Accounting Files and Continuously Executed options are also available when you create a test policy for a composite service.
Once tests have been ordered to generate, a MEG is created on each eligible endpoint SAP. Tests are then generated for this MEG that target other eligible endpoint SAPs within the composite service. Results for individual tests can then be reviewed.
Note: If there is a previously created MEG on one of the service sites (for example, a MEG created for a service before the service was included in a composite service) and the Generate Tests button is selected, tests are not generated. When a MEG with only a subset of the composite service already exists on one of the service SAPs, the generation of tests is blocked. The MEG must be deleted before the CFM tests are generated.
Examples of Ethernet CFM tests for composite services
The following are examples of how the Ethernet CFM test generation rules for composite services are structured to operate.The examples are based on the default test roles for MEPs. The default roles are Hub and both Test Source and Test Target.
The following figure shows a flat topology view of a simple configuration of two VPLSs (VPLS 8 and VPLS 15101) that are connected by a pair of spoke bindings between sites 192.0.2.96 and 192.0.2.65.
Figure 91-2: Composite service connected by spoke bindings
In this configuration, all four SAPs are considered as endpoints. Therefore MEPs are generated on each SAP and they all target each other. A total of twelve tests are generated. Double-clicking on an endpoint opens the interface configuration form and the MEP generated for this particular endpoint is displayed under the MEPs tab. If you then query the MEP’s properties, the Tests tab in the MEP’s configuration form displays the three tests that target the other MEPs in this composite service.
The following figure shows an example of a routed VPLS configuration with a VPLS (VPLS 15104) and a VPRN (VPRN 11). The services are connected by a routed VPLS interface (shown as routed:N/A:0.0).
Figure 91-3: Routed VPLS composite service
In this configuration, site 192.0.2.95 exists on both the VPLS and VPRN service. This is an overlapping site. The test generation rules would normally skip an overlapping site and no MEGs or tests would be generated for that site.
However in this case, the overlap for this site occurs in an unsupported service. The test generation rules for such a configuration will skip the unsupported VPRN service entirely and only generate tests for the supported VPLS, including site 192.0.2.95. Therefore, two MEPs and two tests (targeting each other) will be generated here, one for each of the SAPs on sites 192.0.2.96 and 192.0.2.95.
The test generation logs available in the test suite configuration form (under the Generation Error Logs tab) provide an explanation whenever the test generation rules cause items to be excluded from the tests. In this case, the log would state: “The CFM Composite Services Test Suite skipped the unsupported service”.
The following figure shows an example of a cross-connected VPLS composite service.
Figure 91-4: Cross-connected VPLS composite service
In this configuration, the two VPLSs (VPLS 14 and VPLS 15) are cross-connected by the SAPs CCAG 1-Alpha and CCAG 1-Beta. Both these SAPs originate from site 192.0.2.95, which exists in both services. It is therefore an overlapping site. The test generation rules skip overlapping sites, so no MEGs or tests are generated for any SAPs associated with that site.
Therefore, two MEPs and two tests (targeting each other) will be generated here, one for each of the SAPs on sites 192.0.2.96 and 192.0.2.97.
In addition, there will be two test generation logs available in the Generation Error Logs tab of the test suite configuration form. In this case, the logs would be identical, one stemming from each of the supported VPLSs. The logs would state: “Skipped overlapping service site”.
The following figure shows an example of an SCP-connected VPLS composite service.
Figure 91-5: SCP-connected VPLS composite service
In this configuration, the two VPLSs (VPLS 15105 and VPLS 16101) are joined by an SCP connector between sites 192.0.2.95 and 192.0.2.66. The test generation rules skip any SAPs identified as part of a connector, since they are not endpoints. So no MEGs or tests are generated for either connector SAP.
MEGs and tests will however, be generated for each of the other four SAPs shown in the example. In total, four MEGs and twelve tests will be generated.
In addition, there will be two test generation logs available in the Generation Error Logs tab of the test suite configuration form. In this case again, the logs would be identical, one stemming from each of the supported VPLSs. The logs would state: “Skipped service connecting SAPs”.