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Xapp onboarding and deployment: check section "RIC applications" in https://docs.o-ran-sc.org/projects/o-ran-sc-it-dep/en/latest/installation-guides.html#ric-applications on how to use the dms_cli to onboard and deploy xApps. Onboarding is the act of generating a Helm chart for the xApp from the its xApp descriptor. Using the generated helm chart (which is specific to a particular RIC instance) the xApp can be deployed.
Generally check the read-the-docs pages: https://docs.o-ran-sc.org/en/latest/projects.html#near-realtime-ran-intelligent-controller-ric
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