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DNF must be used to install modular RPMs; yum does not support modularity
Each modular RPM is built with a special
ModularityLabeltag.DNF will not install an RPM with a
ModularityTagunless it can be associated with modulemd metadata from an available repository.
AppStream Lifecycle
Each RHEL AppStream (module stream) has its own lifecycle, which is usually not the full 10-year lifecycle of the Base OS: https://access.redhat.com/support/policy/updates/rhel8-app-streams-life-cycle.
This includes most default streams.Some streams retire within two years (the first RHEL stream retires in April 2021).
SIMP ISO Build
Requirements
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