CompTIA Linux + XK0-006 (V8) Exam Practice Test 2

The immutable attribute prevents any modification or deletion of a file until explicitly removed, while the append-only attribute permits new data to be added but blocks editing or deleting existing content. The sticky bit, setuid, and setgid are special permission bits affecting execution and directory deletion behavior rather than these chattr-managed attributes.

Steadily climbing memory consumption with no corresponding workload increase, eventually triggering the OOM killer, is a memory leak. Swapping describes active use of disk-based virtual memory due to low RAM, high context switching describes excessive CPU time spent switching between processes, a CPU bottleneck describes CPU capacity being the limiting factor, and packet drops describe network-layer loss rather than a gradual memory consumption trend.

An expired TLS certificate causing browser warnings is a certificate issue, while clients still negotiating with an outdated version like TLS 1.0 is obsolete or insecure protocol usage. An SELinux issue concerns security context and policy, a misconfigured package repository concerns software installation sources, and a remote access issue concerns SSH or similar connectivity problems rather than either of these two described symptoms.

The ability to reach the local subnet but not beyond it, with a missing or misconfigured default route, is specifically a gateway/routing issue. A DNS issue would affect name resolution rather than routed reachability, a DHCP issue would affect address assignment, interface misconfiguration generically covers many possible issues, and link down would prevent even local subnet reachability entirely.

Inode exhaustion occurs when a filesystem runs out of inodes, the structures used to track files, even though raw disk space remains available, preventing new file creation. OS filesystem full describes running out of actual space rather than inodes specifically, a partition not writable concerns a mount or permission issue, quota issues concern per-user or per-group space limits, and a package dependency issue is unrelated to filesystem structure exhaustion.

A package requiring a specific, often conflicting, library version that isn't satisfied by what's currently installed is a package dependency issue. OS filesystem full concerns available disk space, server inaccessible concerns broader connectivity or availability, device failure concerns hardware malfunction, and killed processes concerns processes being terminated rather than a version conflict blocking installation.

A webhook is a lightweight HTTP callback a system sends to a specified URL the moment an event occurs, exactly matching this push-based deployment notification. SNMP traps are a similar unsolicited-push concept but specific to the SNMP protocol rather than a general HTTP callback, health checks are periodic probes rather than event-driven pushes, log aggregation centralizes log data, and agent-based monitoring describes installed collection software rather than this specific callback mechanism.

git diff shows the line-by-line differences between the working directory, staged changes, and the last commit. git log shows commit history, git status shows which files are staged or modified without showing line-level content differences, git branch manages branches, and git clone copies an entire repository rather than showing a diff.

Python uses indentation itself to define code blocks, and mixing tabs and spaces inconsistently within the same block causes an IndentationError, a fundamental syntax requirement rather than just a style preference. Data types and structures concern how values are represented, PEP 8 best practices generically cover broader style conventions beyond this specific syntactic requirement, virtual environments concern dependency isolation, and built-in modules are part of the standard library.

Command substitution, using $(foo) or the older backtick syntax, evaluates a command in a subshell and substitutes its output as text, commonly used to capture command results into a variable.

Shift left testing specifically means moving testing and security checks as early as possible in the development process, before merge or deployment. GitOps uses Git as the source of truth for infrastructure state, pipelines generically describe the automated sequence of build and deployment steps, DevSecOps generically describes integrating security throughout the development lifecycle, and version control tracks code changes rather than describing early-stage testing timing specifically.

LUKS2 provides full disk or partition encryption, making the contents unreadable without the correct passphrase or key even if the drive is moved to another system. GPG encrypts individual files or messages rather than whole partitions, OpenSSL implements TLS and general cryptographic operations, WireGuard is a VPN protocol for data in transit, and HMAC provides message authentication rather than data-at-rest encryption.

Requiring both a password and a time-based one-time code from a second factor is multifactor authentication. Password complexity concerns character requirements, password history prevents reuse of prior passwords, restricted shells limit what commands an account can execute, and pam_tally2 tracks failed login attempts rather than requiring a second authentication factor.

/var stores variable data such as logs, spool files, and caches that change frequently during normal operation. /etc holds system configuration files, /usr holds user-installed software and shared resources, /tmp holds temporary files that may be cleared on reboot, and /proc is a virtual filesystem exposing kernel and process information rather than storing persistent variable data.

The ports versus services distinction lets an administrator reference a named, predefined service like http instead of manually specifying its underlying port number. Rich rules provide custom fine-grained syntax, runtime versus permanent configuration concerns persistence of changes, zones group interfaces under trust levels, and the Netfilter module is the underlying kernel packet filtering framework rather than the named-service convenience feature.

CMD specifies the default command a container runs when started, which can be overridden at runtime. FROM specifies the base image, USER specifies which user the container process runs as, ENTRYPOINT defines a command that is harder to override and is often used alongside CMD for default arguments, and pruning is a cleanup operation rather than a Dockerfile instruction.

DHCP automatically assigns IP addresses, subnet masks, and gateway information to clients on a network. DNS resolves hostnames to IP addresses, NTP/PTP synchronize system clocks, HTTP serves web content, and SMTP transfers email rather than assigning network configuration to clients.

at schedules a one-time job to run once at a specified future time. crontab schedules recurring jobs on a fixed schedule, anacron handles periodic jobs on systems that may not be running continuously, nice sets process priority, and jobs lists jobs in the current shell session rather than scheduling a future one-time task.

userdel -r removes both the account and its home directory in one step, while passwd -l locks an account's password without deleting anything, allowing easy reactivation. usermod -aG adds a user to a supplementary group, chage -E sets an account expiration date, and groupdel removes a group rather than describing either of these two account lifecycle actions.

lsof can list open files, including network sockets, and identify which process holds a specific port open. ps and top show general process information without focusing on open file or socket ownership, nice sets process priority, and jobs lists jobs running in the current shell session rather than showing which process holds a specific port.

ddrescue is purpose-built to continue past unreadable sectors during failing-disk recovery, unlike plain dd which typically halts or handles read errors less gracefully. This makes it the preferred tool specifically for rescuing data from failing or damaged drives.

Using - with the cd command returns to the previous working directory without needing to type its full path. ~ represents the home directory, .. represents the parent directory, and . represents the current directory, none of which specifically recall the immediately prior working directory.

ping checks basic reachability, traceroute maps the hop-by-hop path, mtr combines both into a continuous live view, ss displays local socket statistics, and tcpdump captures raw packet contents, each serving a distinct diagnostic purpose.

fsck checks and repairs filesystem inconsistencies, exactly what is needed after an unclean unmount. mkfs creates a new filesystem rather than repairing an existing one, df reports disk space usage, du reports directory space consumption, and xfs_growfs expands an XFS filesystem's size rather than repairing corruption.

nvtop provides a live, graphical view of GPU utilization, memory, and processes, purpose-built for monitoring GPU workloads. lm_sensors reports temperature and voltage sensor readings, dmidecode reports hardware and BIOS information from the system's DMI tables, lshw lists detailed hardware configuration broadly, and ipmitool manages server hardware out-of-band through IPMI rather than showing live GPU utilization specifically.