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- Slides presented to architecture subcommittee to start this project as PoC :
View file name K8S_for_VNFs_And_ONAP_Support.pptx
Version 2 of slides are here:
K8S_for_VNFs_And_ONAP_Support_v2.pptx
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Project (This is sub project of Multi-Cloud as decided by Architecture subcommittee & Multi-Cloud team)
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- Create a Multi-Cloud plugin service that interacts with Cloud regions supporting K8S
- VNF Bring up:
- API: Exposes API to upper layers in ONAP to bring up VNF.
- Currently Proposal 2 (Please see the attached presentation and referenced in Slides/Links section) seems to be the choice.
- Information expected by this plugin :
- K8S deployment information (in the form understood by K8S), which is opaque to rest of ONAP. This information is normally expected to be provided as part of VNF onboarding in CSAR) and some information (variables values) are created part of every instantiation.
- TBD - Is this artifact passed to Multi-Cloud as reference or is it going to be passed as immediate data from the upper layers of ONAP.
- Note that there could be multiple artifacts for a given deployment. For example, EdgeXFoundry requires multiple deployment yaml files (one for each type of container) and multiple service yaml files. Since, there could be many of them, ordering in which they get executed is important. Hence, it is required that the priority order is given in a separate yaml artifact, which is interpreted only by K8S plugin.
- Supported K8S yaml artifacts - Deployment (POD, Daemonset, Stateful set)(, Service, Persistent volume). Others for for future releases.
- Kubernetes templates (artifacts) and variables:
- Since many instances of deployments can be instantiated using same CSAR, it is necessary that they are brought in different namespaces. Namespace name is expected to be part of variables (which is different for different instances).
- And also any template information starting with $.... is replaced from the variables.
- Metadata information collected by upper layers of ONAP
- Cloud region ID
- Set of compute profiles (One for each VDU within the VNF).
- TBD - Is there anything to be passed
- K8S deployment information (in the form understood by K8S), which is opaque to rest of ONAP. This information is normally expected to be provided as part of VNF onboarding in CSAR) and some information (variables values) are created part of every instantiation.
- Functionality:
- Instantiate VNFs that only consist of VMs.
- Instantiate VNFs that only consist of containers
- Instantiate multiple VNFs (some VNFs realized as VMs and some VNFs realized as containers) that communicate with each other on same networks (External Connection Points of various VNFs could be on the same network)
- Reference to newly brought up VNF is stored in A&AI (Which is needed when VNF needs to be brought down, modify the deployment)
- TBD - Should it populate A&AI with reference to each VM & Container instance of VNF? Or one reference to entire VNF instance good enough? Assuming that there is a need for storing reference to each VM/Container instance in A&AI, some exploration is required to see whether this information is made available by K8S API or should it watch for the events from K8S?
- TBD - Is there any other information that this plugin is expected to populate A&AI DB (IP address of each VM/Container instance) and anything else?
- API: Exposes API to upper layers in ONAP to bring up VNF.
- VNF Bring down:
- API: Exposes API function to upper layers in ONAP to terminate VNF
- Functionality: Based on the request coming from upper ONAP layer, it will terminate the VNF that was created earlier.
- Scaling within VNF:
- It leaves the decision of scaling-out and scaling-in of services of the VNF to the K8S controller at the cloud-region.
- (TBD) - How the configuration life cycle management be taken care?
- Should the plugin watch for new replicas being created by K8S and inform APPC, which in turn sends the configuration?
- Or should we let the new instance that is being brought up talk to APP-C or anything else and let it get the latest configuration?
- Healing & Workload Movement (Not part of Casablanca)
- No API is expected as it is assumed that K8S master at the cloud region will take care of this.
- TBD - Is there any information to be populated in the A&AI when some healing or workload movement occurs that the cloud-region.
- VNF scaling: (Not part of Casablanca)
- API : Scaling of entire VNF
- Similar to VNF bring up.
- API : Scaling of entire VNF
- Create Virtual Link:
- API : Exposes API to create virtual link
- Meta data
- Opaque information (Since OVN + SRIOV are chosen, opaque information passed to it is amenable to create networks and subnets as per the OVN/SRIOV Controller capabilities)
- Reference to the newly created network is added to the A&AI.
- If network already exists, it is expected that use count is incremented.
- Functionality:
- Creates network if it does not exist.
- Using OVN/SRIOV CNI API, it will populate remote DHCP/DNS Servers.
- TBD : Need to understand OVN controller and SRIOV controller capabilities and figure out the functionality of this API in this plugin.
- API : Exposes API to create virtual link
- Delete Virtual Link:
- API : Exposes API to delete virtual network
- Functionality:
- If there is no reference to this network (if use count is 0), then using OVN/SRIOV controllers, it deletes the virtual network.
- Create persistent volume
- Create volume that needs to exist across VNF life cycle.
- Delete persistent volume
- Delete volume
- VNF Bring up:
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