Linux Admin

Linux administration: deep working knowledge of enterprise Linux (Red Hat / RHEL, Ubuntu or SUSE) - systemd, journalctl, networking, file systems, user and permission management, performance and troubleshooting tools (top, ss, iostat, strace, tcpdump). Syslog server configuration: hands-on expertise with rsyslog (preferred) or syslog-ng - modules, rulesets, input and output configuration, queues, filtering, templating, and high-availability deployment patterns. Syslog performance tuning: ability to size and tune queues, worker threads, disk-spool, and TCP / TLS parameters; diagnose back-pressure and ingestion latency; interpret syslog server statistics under load.

TLS certificate configuration: configure mutual-TLS authentication between log sources and the syslog server; manage server / client x.509 certificates and certificate authorities; troubleshoot handshake failures with openssl and packet capture.