We will present the results of the commissioning program to establish x-ray lasing and operation of the LCLS-II facility, based on the 4 GeV superconducting accelerator. The commissioning scope included the cryogenic systems, SRF and cryomodules, beam transport and two undulator beamlines serving the hard and soft x-ray programs. The talk will include a discussion of achieved beam performance, both for electron and photon beam and our plans to ramp up to the final objectives. A report of operational issues will be included as well. Finally a brief summary of the status of LCLS-II-HE will be provided.

We designed, built and commissioned a beam diagnostic system based on a short S-band defector and a commercial klystron transmitter. A two feet long transverse-horizontally deflecting S-band rf structure (STCAV2) is installed the LCLS-II post-laser-heater diagnostic beamline at 100 MeV electron beam energy to measure the absolute electron bunch length and to allow time-resolved beam quality measurements such as vertical slide emittance and slice energy spread. The deflector is designed to produce 0.48 MeV peak kick at 300 kW of input power. The klystron transmitter, which uses a commercial solid-state modulator, is installed in the klystron gallery at the grade level. The low-level RF system is based on ATCA and developed in-house. We will report on the overall performance of the project, which was successfully completed, on May 31, 2024.