In 2021, SiGNET Tier-2 computing centre, with over 7000 cores and around 5 PB storage capacity, in 2021 continued its collaboration on international projects and organisations WLCG, EGI, EGI/InSPIRE, Nordugrid. Furthermore, we worked together with other computing centres, like institute's own NSC and Arnes centre. As part of European initiative EuroHPC and Slovenian national supercomputing network SLING, we participated in setting up and maintaining of Vega supercomputer at IZUM in Maribor. The resources of SiGNET enter itself were in 2021 used mainly for data analysis and production of international experiments ATLAS and Belle II, as well as for other department's projects. Some of the resources were also available for other institute members and external collaborators. We have also continued with cooperation in Leonardo project, in setting up one of the three pre-exascale HPC systems in Cineca, Bologna. Apart from maintenance and administration, the department also collaborates in numerous projects related to support, maintenance and planning of the computing infrastructure as well as the development, distribution and deployment of the distributed computing infrastructure.