Cisco Cisco Elastic Services Controller 2.1 Developer's Guide
2.2.2 Stage 2: Activation of a new Configuration
When a configuration is accepted by ESC, the workflows for activating the configuration are submitted
for asynchronous processing. These workflows may update internal states within ESC, and create,
update, or delete resources in the VIM. The ESC Netconf API provides two mechanisms for
communicating the outcome of a configuration activation. These two mechanisms are Event
Notifications and Operational Data, and are discussed below.
for asynchronous processing. These workflows may update internal states within ESC, and create,
update, or delete resources in the VIM. The ESC Netconf API provides two mechanisms for
communicating the outcome of a configuration activation. These two mechanisms are Event
Notifications and Operational Data, and are discussed below.
2.2.2.1 Event Notifications
ESC will generate escEvent Notifications for events that occur during the activation of a new
configuration. A Netconf client can subscribe for these notifications in order to monitor the progress of
the activation. This is the recommended way of monitoring the status of an activation. Each escEvent
notification will have a status of SUCCESS or FAILURE, to report progress during various stages of
activation.
configuration. A Netconf client can subscribe for these notifications in order to monitor the progress of
the activation. This is the recommended way of monitoring the status of an activation. Each escEvent
notification will have a status of SUCCESS or FAILURE, to report progress during various stages of
activation.
2.2.2.2 Operational Data
ESC provides operational data (also called state data in Netconf) through the Netconf interface, which
reflects the current operational state of ESC and the VIM resources that are being managed by ESC.
During various stages of activation, the operational data may be updated to reflect the new state.
reflects the current operational state of ESC and the VIM resources that are being managed by ESC.
During various stages of activation, the operational data may be updated to reflect the new state.
Operational data will be updated after a configuration is successfully activated. Refer to section 5.1 for
details on the impact of specific configuration changes on operational data. Refer to section 3.1 for
general information on reading operational data through the Netconf interface.
details on the impact of specific configuration changes on operational data. Refer to section 3.1 for
general information on reading operational data through the Netconf interface.
2.2.2.3 Activation Failures
If a failure occurs while activating the configuration change, the operational data may be left in a state
that is inconsistent with the configuration. Therefore, when a failure occurs it may be necessary for the
Netconf client to revert the ESC configuration, or for an operator to clean up the VIM configuration, in
order to bring ESC and the VIM back to a consistent operational state. Refer to section 5.1 for
instructions on handling activation failures for specific workflows.
that is inconsistent with the configuration. Therefore, when a failure occurs it may be necessary for the
Netconf client to revert the ESC configuration, or for an operator to clean up the VIM configuration, in
order to bring ESC and the VIM back to a consistent operational state. Refer to section 5.1 for
instructions on handling activation failures for specific workflows.
2.2.3 Configuration Workflows
ESC uses configuration workflows to manage configuration changes. The supported workflows are
defined in detail in section 5.1. In general, a separate Netconf edit-config request should be sent for
each specific configuration workflow. So for example, one service deployment would map to a single
workflow, and therefore a single Netconf edit-config request.
defined in detail in section 5.1. In general, a separate Netconf edit-config request should be sent for
each specific configuration workflow. So for example, one service deployment would map to a single
workflow, and therefore a single Netconf edit-config request.
There are some workflows however that can be combined into a single Netconf edit-config request. See
the next section for more details on combining workflows.
the next section for more details on combining workflows.
2.2.4 Combining Workflows
ESC supports combining some workflows into a single Netconf edit-config request.