As part of the recently concluded ThetaGPU maintenance, all nodes save for the single-gpu host have been upgraded to the latest supported OS release. You are advised to recompile/rebuild any applications or libraries built on the previous OS version. Also note that modules is the primary source for software, so if you encounter issues finding dependencies etc., please ensure your session is loading modules properly. Bash users in particular should check that their ~/.bashrc is sourcing /etc/bash.bashrc, and that any job scripts are explicitly sourcing /etc/profile. In the coming days, the single-gpu queue will be transitioned over to the new release.