Evidence-Gated Migration from Virtual ZMQ to UHD-Enabled gNB: Reproducible Build and USRP X310 Container Integration in a 5G/O-RAN Testbed

Migrating an experimental 5G/O-RAN gNB from a virtual ZeroMQ (ZMQ) radio interface to a Universal Hardware Driver (UHD)-enabled software-defined radio environment introduces source-provenance, toolchain, application binary interface (ABI), packaging and operational-safety risks. This technical preprint reports an evidence-gated migration of a modified srsRAN Project gNB towards a USRP X310 attached to a virtualised testbed host. A seven-component scientific source-tree recovery gate preceded an isolated Ubuntu 24.04 build with UHD, ZMQ and export support enabled. The compiled gNB passed linked-library inspection and was packaged into a separate inert Docker image after an ABI incompatibility with an existing Ubuntu 22.04 baseline image was demonstrated. A dedicated diagnostic image resolved the additional dependencies of the UHD discovery utility and successfully identified the physical X310 through the host network namespace. A subsequent static audit preserved source and object-file hashes and identified unresolved radio-frequency (RF), user-equipment (UE), core-network and scientific-control gates. The contribution is an auditable engineering workflow and an explicitly bounded integration result, not proof of over-the-air 5G service, E2SM-RC actuation, real RLC-queue measurement or closed-loop PI performance on hardware. No gNB radio session, RF transmission, UE attachment or scientific UDP experiment was conducted in the reported hardware-integration stages.