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Home > Training > Unix > Linux Systems Administration III Training

Linux Systems Administration III Training

Course#: GL254

This GL254 course is designed to follow an identical set of topics as the Red Hat® RH254, RH255 RHCE exam prep courses with the added benefit of very comprehensive lab exercises and detailed lecture material. The Red Hat Enterprise Linux (RHEL) system administration topics covered in this course along with the GL199 course cover the certification objects of the Red Hat Certified Engineer (RHCE) exam. This course builds upon a foundation of core Linux systems administration principles and skills. Students will advance their Linux systems administration knowledge. The course will focus on helping students optimize system administration skills using automation techniques and deploy commonly used network services. Once this course is completed students will know how to deploy critical network services in a secure fashion.

Red Hat® is a registered trademark of Red Hat, Inc. and its use by Guru Labs, L.C. does not imply association or sponsorship by Red Hat, Inc.


Students should have skill equal to those taught in the GL124 "Red Hat Enterprise Linux Systems Admin I" and GL134 "Red Hat Enterprise Linux Systems Admin I" courses. Also these prerequisite skills are taught in the GL120 "Linux Fundamentals" and GL250 "Enterprise Linux Systems Administration" courses.


4 Days

Outline of GL254 Linux Systems Administration III Training

1. Enhance User Security

  • Kerberos Concepts
  • Kerberos Components
  • Kerberos Principals
  • Overall Goals for Users
  • Authentication Process
  • Install krb5.conf on Clients
  • Client PAM Configuration
  • Signing In to Kerberos
  • Viewing Tickets
  • Removing Tickets
  • Passwords
  • Changing Passwords
  • Giving Others Access
  • SSH Key Management
  • ssh-agent
  • OpenSSH and Kerberos

Lab Tasks

  • SSH Key-based User Authentication
  • Using ssh-agent
  • Kerberos Client Setup
  • OpenSSH with Kerberos

2. Bash Scripting and Tools

  • Shell Script Strengths and Weaknesses
  • Example Shell Script
  • Positional Parameters
  • Input & Output
  • Doing Math
  • Comparisons with test
  • Exit Status
  • Conditional Statements
  • Flow Control: case
  • The for Loop
  • The while and until Loops

Lab Tasks

  • Writing a Shell Script

3. File Security with GnuPG

  • GPG - GNU Privacy Guard

Lab Tasks

  • File Encryption with GPG

4. Software Management

  • RPM Package Files
  • Source RPMs
  • Using Source RPMs
  • Installing Source RPM Packages
  • Creating Support Files
  • The Spec file
  • The Header Stanza
  • Prep, Build, and Install
  • The Files Section
  • Optional Script Section(s)
  • The Changelog Section
  • Building Packages
  • Digitally Signing Packages
  • Revising a Package
  • RPM Development Tools
  • Yum Plugins
  • Dealing With RPM & YUM Digest Changes

Lab Tasks

  • rpmdevtools and Simple RPM Creation

5. Network Monitoring

  • tcpdump and wireshark
  • Information from netstat and ss
  • lsof and fuser
  • nmap

Lab Tasks

  • Network Tools
  • NMAP

6. Route Network Traffic

  • Configuring the Kernel via /proc/
  • Tuning Kernel Network Settings
  • Linux as a Router
  • Configuring Routing Tables
  • IP to MAC Address Mapping with ARP

Lab Tasks

  • Adjusting Kernel Options

7. Secure Network Traffic

  • SSH Port Forwarding
  • Persistent Port Forwarding Configuration
  • Netfilter: Stateful Packet Filter Firewall
  • Netfilter Concepts
  • Using the iptables Command
  • Common match_specs
  • Address Translation
  • Configuring NAT and PAT
  • NAT Limitations
  • Security Using NAT and PAT
  • Detecting NAT

Lab Tasks

  • Tunneling TCP connections over SSH
  • Securing Services with Netfilter

8. NTP Server Configuration

  • Managing Network-Wide Time
  • Continual Time Sync with NTP
  • Configuring NTP Clients
  • Useful NTP Commands

Lab Tasks

  • NTP Client Configuration

9. System Monitoring and Logs

  • Filesystem Structures
  • Determining Disk Usage With df and du
  • Filesystem Maintenance
  • Corrupt Filesystems
  • Troubleshooting Incorrect File Permissions
  • System Status - Memory
  • System Status - I/O
  • System Status - CPU
  • Viewing Processes
  • Performance Trending with sar
  • System Logging
  • Rsyslog
  • /etc/rsyslog.conf
  • Log Management
  • Log Anomaly Detector

Lab Tasks

  • Setting up a Full Debug Logfile
  • Remote Syslog Configuration
  • System Activity Reporter

10. Centralized and Secure Storage

  • SAN Multipathing
  • Multipath Configuration
  • Multipathing Best Practices
  • iSCSI Architecture
  • Open-iSCSI Initiator Implementation
  • iSCSI Initiator Discovery
  • iSCSI Initiator Node Administration
  • Mounting iSCSI Targets at Boot
  • iSCSI Multipathing Considerations
  • File Encryption With encfs
  • Linux Unified Key Setup (LUKS)

Lab Tasks

  • iSCSI Initiator Configuration
  • LUKS-on-disk format Encrypted Filesystem

11. SSL-encapsulated Web Services

  • Apache Architecture
  • Adding Modules to Apache
  • Apache Configuration Files
  • httpd.conf - Server Settings
  • httpd.conf - Main Configuration
  • Symmetric Encryption Algorithms
  • Asymmetric Encryption Algorithms
  • Digital Certificates
  • SSL Using

Lab Tasks

  • Apache Architecture
  • Apache Content
  • Using SSL Certificates with Apache

12. Web Server Additional Configuration

  • Virtual Hosting DNS Implications
  • httpd.conf - VirtualHost Configuration
  • Name-based Virtual Host
  • Apache Logging
  • Delegating Administration
  • Directory Protection
  • Directory Protection with AllowOverride
  • Common Uses for .htaccess
  • Configuring CGI

Lab Tasks

  • Configuring Virtual Hosts
  • Using .htaccess Files
  • CGI Scripts in Apache

13. Basic SMTP Configuration

  • Postfix Features
  • Postfix Components
  • Postfix Configuration
  • Postfix Map Types
  • Postfix Pattern Matching
  • Virtual Domains
  • Configuration Commands
  • Management Commands
  • Postfix, Relaying and SMTP AUTH
  • SMTP AUTH Server and Relay Control

Lab Tasks

  • Configuring Postfix
  • Postfix Network Configuration
  • Postfix Virtual Host Configuration

14. Caching-Only DNS Server

  • Naming Services
  • The Domain Name Space
  • Delegation and Zones
  • Server Roles
  • Resolving Names
  • Resolving IP Addresses
  • Basic BIND Administration
  • Configuring the Resolver
  • Testing Resolution
  • Creating a Site-Wide Cache
  • SOA - Start of Authority
  • A & PTR - Address & Pointer Records
  • NS - Name Server
  • CNAME & MX - Alias & Mail Host

Lab Tasks

  • Caching-only DNS

15. File Sharing with NFS

  • File Sharing via NFS
  • NFSv4
  • NFS Clients
  • NFS Server Configuration
  • Implementing NFSv4

Lab Tasks

  • NFS Server Configuration

16. File Sharing with CIFS

  • Samba Daemons
  • Accessing Windows/Samba Shares from Linux
  • Samba Utilities
  • Samba Configuration Files
  • The smb.conf File
  • Mapping Permissions and ACLs
  • Mapping Linux Concepts
  • Mapping Users
  • Share Authentication
  • User-Level Access
  • Samba Account Database
  • User Share Restrictions

Lab Tasks

  • Samba Share-Level Access
  • Samba User-Level Access
  • Samba Group Shares

17. File Sharing with FTP

  • The FTP Protocol
  • Active Mode FTP
  • Passive Mode FTP
  • vsftpd
  • Anonymous FTP with vsftpd

Lab Tasks

  • Configuring vsftpd

18. Troubleshooting Boot Process

  • Booting Linux on PCs
  • GRUB Configuration
  • Boot Parameters
  • Initial ramdisk
  • /sbin/init
  • System Init Styles
  • Linux Runlevels
  • /etc/inittab
  • /etc/rc.d/rc.sysinit
  • Runlevel Implementation
  • System Configuration Files
  • Typical SysV Init Script
  • The /etc/rc.local File
  • Shutdown and Reboot
  • Rescue Environment

Lab Tasks

  • Boot Process
  • Recovering Damaged MBR
  • Introduction to Troubleshooting Labs
  • Troubleshooting Practice: Boot Process


We regularly offer classes in these and other cities. Atlanta, Austin, Baltimore, Calgary, Chicago, Cleveland, Dallas, Denver, Detroit, Houston, Jacksonville, Miami, Montreal, New York City, Orlando, Ottawa, Philadelphia, Phoenix, Pittsburgh, Seattle, Toronto, Vancouver, Washington DC.
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