CompTIA Linux+ (XK0-004)

Frank introduces the Linux+ certification (XK0-004) and outlines exam preparation, scheduling, and the testing format: a monitored environment, one to two hours, multiple choice, fill-in-the-blank, and puzzle questions.

Master Linux administration by exploring command line basics, user management, storage and file systems, kernel and boot processes, networking, security, scripting, and installation for exam readiness.

Explore the Linux design philosophy and open source roots, the kernel and GNU project, and how distros—from Debian and Ubuntu to Red Hat and CentOS—shape server and desktop use.

Explore the command line interface and the shell, learn command structure and options, and practice core Linux commands like ls, pwd, and cp.

Practice shell commands and file system navigation in a Linux environment, using echo, pwd, ls, cd, touch, and copying files while exploring permissions in /var/log and reading logs with less.

Learn to access and use Linux documentation with man pages, the help and --help options, whatis, apropos, and info, then consult vendor websites and release notes for how-tos.

Explore how to manage users and groups in Linux, elevate to root with sudo and su, configure sudoers, and implement least privilege with account profiles and service accounts.

Create, modify, and delete user accounts with useradd, usermod, and userdel, manage home directories and shells, and understand /etc/shadow password storage and aging policy.

Create, modify, and delete groups to manage multiple users. Explore /etc/group definitions, primary versus secondary memberships, and commands like groupadd, usermod, groupmod, and groupdel for access control.

Query users and groups to verify identities and permissions with id, who, and w; audit login history with last to troubleshoot access and file permissions.

Learn how to harness the Unix philosophy by mastering standard input, output, and error streams, and connect tools with redirection, piping, and common utilities like grep, diff, and wc.

Explore Linux file and directory permissions and ownership, including user/group/other access, read/write/execute rights, symbolic and numeric chmod modes, and the role of umask in creation.

Examine file ownership and group attributes, using chown to transfer ownership or set the group; root can change ownership for any file, while the owner can adjust its group.

Explore Linux special permissions and attributes, including setuid, setgid, and the sticky bit, plus immutable flags and ACLs for fine-grained access control.

Develop a systematic troubleshooting approach in Linux, starting with identifying the problem, analyzing causes, and testing solutions for permission issues. Use iterative cycles and back out changes as needed.

Identify attached drives, create partitions and file systems, mount them, and map devices to directories using labels and GPT/MBR while understanding the Linux kernel, inodes, and journaling.

Understand how the device mapper abstracts physical drives into volume groups and logical volumes for scalable storage. Use pv, vg, and lv tools to create, extend, and snapshot volumes.

Learn to create logical volumes, install file systems, and mount them to dedicated mount points; configure automatic mounting via /etc/fstab with security and access controls.

Discover how to verify mounts, inspect /proc for partitions, and grow file systems on logical volumes using fsck, resize2fs, lvextend, and related tools.

Navigate the Linux directory structure by identifying file types, mastering absolute and relative paths, and exploring key directories such as /etc, /dev, /usr, and /var to manage files and permissions.

Explore troubleshooting storage issues using df, du, iostat, and quotas to identify bottlenecks and per-user limits. Learn to diagnose latency, balance workload, and enforce quotas with rep quota.

Learn to edit text files on Linux using vim, nano, and gedit, mastering command-line editing, navigation, copy-paste, undo, search, and saving, with basic file management.

Explore file search in Linux using locate and find, comparing database-based speed with real filesystem traversal. Update the locate database regularly and handle permissions to minimize errors while locating files.

Master core Linux file and directory operations, using cat, head, tail, and less to view; and cp, mv, rm, touch, and mkdir to manage files.

Explore core text processing and file manipulation in Linux shells: echo to standard output, tr, wc, sort, cut, paste, diff, grep, awk, sed, and linking with ln.

Explore how unix streams—standard input, standard output, and standard error—are redirected and piped to combine small tools like grep, wc, and xargs into powerful workflows.

Explore the Linux kernel, its role as the operating system heart, and how to add, monitor, and configure modules in the running kernel using system calls.

Learn how Linux uses a monolithic kernel with boot-time modules and dynamic loading via modprobe, insmod, and depmod to add or remove drivers like Bluetooth USB.

Examine the proc filesystem and kernel messages to monitor kernel modules and device detection, boot parameters, and kernel version, using dmesg, /proc, and related logs.

Trace the boot sequence from firmware through bootloader to kernel and systemd, covering BIOS/UEFI, MBR vs GPT, and grub2 with initramfs. Learn to configure grub and troubleshoot boot failures.

Configure Grub introduces the Grub 2 bootloader, templates in grub.d, and rebuilding grub config to control boot menus. It covers timeouts, boot parameters, and rescue options for BIOS and EFI.

Configure localization options in Linux by setting time zones, locales, keyboard maps, and encoding, while understanding systemd's role in service management and time synchronization.

Explore linux graphical interfaces, choosing from Genome, KDE plasma, Matai, Cinnamon, and more, and understand X Windows and Wayland display servers, compositor architecture, and remote desktop and accessibility options.

Explore how Linux manages services and daemon processes with systemd, unit files and targets, covering run levels, enabling, starting, stopping, and isolating boot configurations.

Explore how Linux manages processes, diagnoses latency and bottlenecks with top, ps, pgrep, and lsof, and controls jobs, signals, and open files.

Diagnose cpu and memory issues by analyzing per-process usage, kernel metrics via /proc, uptime, run queue, and swap, using top, vmstat, and sar to prevent bottlenecks.

Explore the kernel’s device interface and how drivers enable hardware, from USB devices and NIC adapters to SATA and SCSI storage, with GPIO and PCI bus context.

Explore how linux manages devices via /proc/devices and /dev, use udev rules for predictable hot-plug naming, and configure cups printing with queues, filters, and ppd files.

Explore how to discover hardware with command-line tools, list usb and pci devices, view device IDs and storage allocations, and monitor the print queue and kernel logs for debugging.

Troubleshoot hardware issues in Linux by ensuring the kernel recognizes devices, checking connections, locales, and drivers, and managing printers, keyboards, memory, and video.