Sequencing rules in SOL006 LCM scripts
The following action point needs to be addressed as part of SOL006.
SOL95-AP5 - Clarify whether SOL006 should specify the sequencing rules between scripts triggered on internal and external events.
In ETSI GS NFV-IFA 011, the definition of the "LifeCycleManagementScript" information element of the VNFD associates scripts with events, where an event can be an external or an internal stimulus.
In SOL001, external stimuli are mapped to TOSCA operations corresponding to the VNF LCM operations defined in ETSI GS NFV-IFA 007 and internal stimuli are mapped to preamble and postamble of these TOSCA operations. If an LCM script is associated to a TOSCA operation that represents a preamble or a postamble to a VNF LCM operation, the script is executed before or after the execution of the VNF LCM operation implementation, respectively.
It looks like there are actually two issues w.r.t. how SOL006 implements IFA011 concepts.
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The first issue is that SOL006 defines a single event type internal-lifecycle-management-script-event the specification of which – in the common-definitions.yang module) seems to exclude external stimuli.
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The second issue (which is the one originally targeted by the action point) is that SOL006 does not specify the order of execution between LCM scripts attached to an external stimuli et LCM scripts attached to an internal stimuli. This issue can’t be fixed without fixing the 1st one.