Description of problem: - ceph-mgr crashing with the error "RuntimeError: uid/gid not found" when there is low/full space on /var/tmp. The following improvement is needed: 1. The code needs to handle the above exception. 2. "ceph health detail" should report the warnings prior to stop working mgr / Alert when disk space is low. 3. What should be our recommendation[1] for the size of "/var/tmp"(in case of separate mount point) and "/tmp". Version-Release number of selected component (if applicable): - Ceph version 16.2.7-112 How reproducible: Yes Steps to Reproduce: 1. Install RHEL with separate /var/tmp directory and install RHCS 5. 2. Find the active mgr and fill the directory /var/tmp 3. Execute "ceph health detail". 4. Run Apache Benchmark: ab -c100 -n1000 "https://<dashboard_url>:<dashboard_port>" 5. Access the dashboard and check the active mgr logs. Actual results: - Dashboard is not accessing. Expected results: - Mgr/cherrypy/code should handle the exception in case of high disk usage. Additional info: [1] Documentation Improvement: https://access.redhat.com/documentation/en-us/red_hat_ceph_storage/5/html/hardware_guide/minimum-hardware-recommendations-for-containerized-ceph_hw