Shells and Shell Scripting

Key Knowledge Areas:
-Set environment variables (e.g. PATH) at login or when spawning a new shell.
-Write Bash functions for frequently used sequences of commands.
-Maintain skeleton directories for new user accounts.
-Set command search path with the proper directory.

The following is a partial list of the used files, terms and utilities:
-.
-source
-/etc/bash.bashrc
-/etc/profile
-env
-export
-set
-unset
-~/.bash_profile
-~/.bash_login
-~/.profile
-~/.bashrc
-~/.bash_logout
-function
-alias

Key Knowledge Areas:
-Use standard sh syntax (loops, tests).
-Use command substitution.
-Test return values for success or failure or other information provided by a command.
-Execute chained commands.
-Perform conditional mailing to the superuser.
-Correctly select the script interpreter through the shebang (#!) line.
-Manage the location, ownership, execution and suid-rights of scripts.

The following is a partial list of the used files, terms and utilities:
-for
-while
-test
-if
-read
-seq
-exec
-||
-&&

User Interfaces and Desktops

Key Knowledge Areas:
-Understanding of the X11 architecture.
-Basic understanding and knowledge of the X Window configuration file.
-Overwrite specific aspects of Xorg configuration, such as keyboard layout.
-Understand the components of desktop environments, such as display managers and window managers.
-Manage access to the X server and display applications on remote X servers.
-Awareness of Wayland.

The following is a partial list of the used files, terms and utilities:
-/etc/X11/xorg.conf
-/etc/X11/xorg.conf.d/
-~/.xsession-errors
-xhost
-xauth
-DISPLAY
-X

The following is a partial list of the used files, terms and utilities:
-KDE
-Gnome
-Xfce
-X11
-XDMCP
-VNC
-Spice
-RDP

Weight: 1
Description: Demonstrate knowledge and awareness of accessibility technologies.

Key Knowledge Areas:
-Basic knowledge of visual settings and themes.
-Basic knowledge of assistive technology.

The following is a partial list of the used files, terms and utilities:
-High Contrast/Large Print Desktop Themes.
-Screen Reader.
-Braille Display.
-Screen Magnifier.
-On-Screen Keyboard.
-Sticky/Repeat keys.
-Slow/Bounce/Toggle keys.
-Mouse keys.
-Gestures.
-Voice recognition.

Administrative Tasks

Weight: 5
Description: Candidates should be able to add, remove, suspend and change user accounts.

Key Knowledge Areas:
-Add, modify and remove users and groups.
-Manage user/group info in password/group databases.
-Create and manage special purpose and limited accounts.

The following is a partial list of the used files, terms and utilities:
-/etc/passwd
-/etc/shadow
-/etc/group
-/etc/skel/
-chage
-getent
-groupadd
-groupdel
-groupmod
-passwd
-useradd
-userdel
-usermod

Weight: 4
Description: Candidates should be able to use cron and systemd timers to run jobs at regular intervals and to use at to run jobs at a specific time.

Key Knowledge Areas:
-Manage cron and at jobs.
-Configure user access to cron and at services.
-Understand systemd timer units.

The following is a partial list of the used files, terms and utilities:
-/etc/cron.{d,daily,hourly,monthly,weekly}/
-/etc/at.deny
-/etc/at.allow
-/etc/crontab
-/etc/cron.allow
-/etc/cron.deny
-/var/spool/cron/
-crontab
-at
-atq
-atrm
-systemctl
-systemd-run

Weight: 3
Description: Candidates should be able to localize a system in a different language than English. As well, an understanding of why LANG=C is useful when scripting.

Key Knowledge Areas:
-Configure locale settings and environment variables.
-Configure timezone settings and environment variables.

The following is a partial list of the used files, terms and utilities:
-/etc/timezone
-/etc/localtime
-/usr/share/zoneinfo/
-LC_*
-LC_ALL
-LANG
-TZ
-/usr/bin/locale
-tzselect
-timedatectl
-date
-iconv
-UTF-8
-ISO-8859
-ASCII
-Unicode

Essential System Services

Weight: 3
Description: Candidates should be able to properly maintain the system time and synchronize the clock via NTP.

Key Knowledge Areas:
-Set the system date and time.
-Set the hardware clock to the correct time in UTC.
-Configure the correct timezone.
-Basic NTP configuration using ntpd and chrony.
-Knowledge of using the pool.ntp.org service.
-Awareness of the ntpq command.

The following is a partial list of the used files, terms and utilities:
-/usr/share/zoneinfo/
-/etc/timezone
-/etc/localtime
-/etc/ntp.conf
-/etc/chrony.conf
-date
-hwclock
-timedatectl
-ntpd
-ntpdate
-chronyc
-pool.ntp.org

Weight: 4
Description: Candidates should be able to configure rsyslog. This objective also includes configuring the logging daemon to send log output to a central log server or accept log output as a central log server. Use of the systemd journal subsystem is covered. Also, awareness of syslog and syslog-ng as alternative logging systems is included.

Key Knowledge Areas:
-Basic configuration of rsyslog.
-Understanding of standard facilities, priorities and actions.
-Query the systemd journal.
-Filter systemd journal data by criteria such as date, service or priority.
-Configure persistent systemd journal storage and journal size.
-Delete old systemd journal data.
-Retrieve systemd journal data from a rescue system or file system copy.
-Understand interaction of rsyslog with systemd-journald.
-Configuration of logrotate.
-Awareness of syslog and syslog-ng.

Terms and Utilities:
-/etc/rsyslog.conf
-/var/log/
-logger
-logrotate
-/etc/logrotate.conf
-/etc/logrotate.d/
-journalctl
-systemd-cat
-/etc/systemd/journald.conf
-/var/log/journal/

Weight: 3
Description: Candidates should be aware of the commonly available MTA programs and be able to perform basic forward and alias configuration on a client host. Other configuration files are not covered.

Key Knowledge Areas:
-Create e-mail aliases.
-Configure e-mail forwarding.
-Knowledge of commonly available MTA programs (postfix, sendmail, exim) (no configuration).

Terms and Utilities:
-~/.forward
-sendmail emulation layer commands
-newaliases
-mail
-mailq
-postfix
-sendmail
-exim

Weight: 2
Description: Candidates should be able to manage print queues and user print jobs using CUPS and the LPD compatibility interface.

Key Knowledge Areas:
-Basic CUPS configuration (for local and remote printers).
-Manage user print queues.
-Troubleshoot general printing problems.
-Add and remove jobs from configured printer queues.

The following is a partial list of the used files, terms and utilities:
-CUPS configuration files, tools and utilities
-/etc/cups/
-lpd legacy interface (lpr, lprm, lpq)

Networking Fundamentals

Weight: 4
Description: Candidates should demonstrate a proper understanding of TCP/IP network fundamentals.

Key Knowledge Areas:
-Demonstrate an understanding of network masks and CIDR notation.
-Knowledge of the differences between private and public "dotted quad" IP addresses.
- Knowledge about common TCP and UDP ports and services (20, 21, 22, 23, 25, 53, 80, 110, 123, 139, 143, 161, 162, 389, 443, 465, 514, 636, 993, 995).
- Knowledge about the differences and major features of UDP, TCP and ICMP.
-Knowledge of the major differences between IPv4 and IPv6.
-Knowledge of the basic features of IPv6.

The following is a partial list of the used files, terms and utilities:
-/etc/services
-IPv4, IPv6
-Subnetting
-TCP, UDP, ICMP

Weight: 4
Description: Candidates should be able to manage the persistent network configuration of a Linux host.

Key Knowledge Areas:
-Understand basic TCP/IP host configuration.
-Configure ethernet and wi-fi network using NetworkManager.
-Awareness of systemd-networkd.

The following is a partial list of the used files, terms and utilities:
-/etc/hostname
-/etc/hosts
-/etc/nsswitch.conf
-/etc/resolv.conf
-nmcli
-hostnamectl
-ifup
- ifdown

Weight: 4
Description: Candidates should be able to troubleshoot networking issues on client hosts.

Key Knowledge Areas:
-Manually configure network interfaces, including viewing and changing the configuration of network interfaces using iproute2.
-Manually configure routing, including viewing and changing routing tables and setting the default route using iproute2.
-Debug problems associated with the network configuration.

The following is a partial list of the used files, terms and utilities:
-ip
-hostname
-ss
-ping
-ping6
-traceroute
-traceroute6
-tracepath
-tracepath6
-netcat
-ifconfig
-netstat
-route

Weight: 2
Description: Candidates should be able to configure DNS on a client host.

Key Knowledge Areas:
-Query remote DNS servers.
-Configure local name resolution and use remote DNS servers.
-Modify the order in which name resolution is done.
-Debug errors related to name resolution.
-Awareness of systemd-resolved.

The following is a partial list of the used files, terms and utilities:
-/etc/hosts
-/etc/resolv.conf
-/etc/nsswitch.conf
-host
-dig
-getent

Security

Weight: 3
Description: Candidates should know how to review system configuration to ensure host security in accordance with local security policies.

Key Knowledge Areas:
-Audit a system to find files with the suid/sgid bit set.
-Set or change user passwords and password aging information.
-Being able to use nmap and netstat to discover open ports on a system.
-Set up limits on user logins, processes and memory usage.
-Determine which users have logged in to the system or are currently logged in.
-Basic sudo configuration and usage.

The following is a partial list of the used files, terms and utilities:
-find
-passwd
-fuser
-lsof
-nmap
-chage
-netstat
-sudo
-/etc/sudoers
-su
-usermod
-ulimit
-who, w, last

Weight: 3
Description: Candidates should know how to set up a basic level of host security.

Key Knowledge Areas:
-Awareness of shadow passwords and how they work.
-Turn off network services not in use.
-Understand the role of TCP wrappers.

The following is a partial list of the used files, terms and utilities:
-/etc/nologin
-/etc/passwd
-/etc/shadow
-/etc/xinetd.d/
-/etc/xinetd.conf
-systemd.socket
-/etc/inittab
-/etc/init.d/
-/etc/hosts.allow
- /etc/hosts.deny

Weight: 4
Description: The candidate should be able to use public key techniques to secure data and communication.

Key Knowledge Areas:
-Perform basic OpenSSH 2 client configuration and usage.
-Understand the role of OpenSSH 2 server host keys.
-Perform basic GnuPG configuration, usage and revocation.
-Use GPG to encrypt, decrypt, sign and verify files.
-Understand SSH port tunnels (including X11 tunnels).

The following is a partial list of the used files, terms and utilities:
-ssh
-ssh-keygen
-ssh-agent
-ssh-add
-~/.ssh/id_rsa and id_rsa.pub
-~/.ssh/id_dsa and id_dsa.pub
-~/.ssh/id_ecdsa and id_ecdsa.pub
-~/.ssh/id_ed25519 and id_ed25519.pub
-/etc/ssh/ssh_host_rsa_key and ssh_host_rsa_key.pub
-/etc/ssh/ssh_host_dsa_key and ssh_host_dsa_key.pub
-/etc/ssh/ssh_host_ecdsa_key and ssh_host_ecdsa_key.pub
-/etc/ssh/ssh_host_ed25519_key and ssh_host_ed25519_key.pub
-~/.ssh/authorized_keys
-ssh_known_hosts
-gpg
-gpg-agent
-~/.gnupg/