GL314 · 5 days · 17+ hrs hands-on labs

Linux Troubleshooting

Available for RHEL· SLES

Build the diagnostic instincts and root-cause analysis skills that separate reactive firefighters from effective Linux troubleshooters. This lab-intensive course dedicates roughly 75 percent of class time to hands-on exercises, with over 120 independent troubleshooting scenarios organized by topic and progressive difficulty, giving students real practice diagnosing and resolving failures across the full systems administration stack.

Course content spans troubleshooting methodology, essential diagnostic tools such as strace, tcpdump, lsof, and Wireshark, rescue and recovery procedures, boot process diagnosis, filesystem and storage troubleshooting including LVM and software RAID, network configuration and connectivity issues, firewall analysis, and service-level troubleshooting for DNS, NFS, Samba, Apache, Postfix, MariaDB, and other enterprise services. Students also cover kernel module management, performance analysis with vmstat and iostat, user authentication with PAM and LDAP, and SELinux policy troubleshooting.

Each topic group includes self-paced lab scenarios with progressive hints, allowing students to work at their own level and focus on areas most relevant to their environment. Labs run on your choice of RHEL or SLES, with courseware cross-reference where the distributions differ.

Who Should Attend

Intermediate to advanced Linux system administrators, DevOps engineers, site reliability engineers, and IT professionals responsible for maintaining enterprise Linux servers who want to strengthen their diagnostic and problem-resolution skills across system, network, and service domains.

Skills You'll Gain

Apply structured troubleshooting methodology to diagnose and resolve Linux system problems
Use strace, ltrace, lsof, and fuser to trace system calls, library calls, and open files
Boot into rescue environments and recover unbootable systems using chroot, fsck, and grub2-install
Troubleshoot the Linux boot process including GRUB 2, systemd targets, and kernel initialization
Diagnose and resolve filesystem problems including full disks, exhausted inodes, and corruption
Troubleshoot network connectivity using ip, ss, nmap, netcat, tcpdump, and Wireshark
Identify and resolve firewall issues with iptables and Netfilter rule analysis
Troubleshoot network services including DNS, NFS, Samba, Apache, Postfix, and MariaDB
Diagnose performance bottlenecks using vmstat, iostat, pidstat, and top
Manage and troubleshoot kernel modules, LVM volumes, and software RAID arrays
Troubleshoot user authentication problems involving PAM, LDAP, and account expiration
Analyze system and application logs using journalctl and rsyslog to isolate root causes

Chapters & Labs

14 labs · 17+ hours hands-on
  1. Troubleshooting Methodology
  2. Troubleshooting Tools 4 labs · 100 min
  3. Rescue Environments 3 labs · 40 min
  4. Topic Group 1 1 lab · 120 min
  5. Topic Group 2 1 lab · 120 min
  6. Topic Group 3 1 lab · 120 min
  7. Topic Group 4 1 lab · 120 min
  8. Topic Group 5 1 lab · 120 min
  9. Topic Group 6 1 lab · 120 min
  10. Topic Group 7 1 lab · 120 min

Prerequisites

Solid experience with Linux system administration including package management, networking, storage, and service management. GL120 (Linux Fundamentals) and GL250 (Enterprise Linux Systems Administration) or equivalent experience recommended.