702-100 Exam Dumps - LPI Certification Questions and Answers

The tar command is used to create or extract compressed archive files on BSD systems. It can handle various compression formats, such as gzip, bzip2, xz, and lzma. The tar command takes different options to specify the compression type, such as -z for gzip, -j for bzip2, -J for xz, and -Z for lzma. The other options are not related to compression, but to other functions of the tar command, such as -x for extracting, -c for creating, and -v for verbose output. References:

• [tar(1) - OpenBSD manual pages]
• [FreeBSD Handbook - Chapter 3. Unix Basics]
• [FreeBSD Handbook - Chapter 18. Storage]

The question mark (?) is a special character in regular expressions that modifies the preceding expression to match zero or one times. For example, the regular expression colou?r matches both color and colour, but not colouur or colr. The question mark is also used to make an expression non-greedy, meaning that it will match the shortest possible string instead of the longest. For example, the regular expression <.?> matches the first pair of angle brackets in a string, while <.> matches the entire string enclosed by the outermost pair of angle brackets. References:

• Regular expression - Wikipedia, section “Basic concepts”
• How to write Regular Expressions? - GeeksforGeeks, section “Special Characters”

The command df -h displays the disk space usage of all mounted filesystems in a human-readable format. It shows the size, used, available, and percentage of each filesystem, as well as the mount point. This command can be used to check the local filesystems that are currently mounted.

https://unix.stackexchange.com/questions/24182/how-to-get-the-complete-and-exact-list-of-mounted-filesystems-in-linux

https://www.tecmint.com/find-mounted-file-systems-in-linux/

https://itslinuxfoss.com/check-filesystem-mounted-linux/

The directories that contain start scripts for services on FreeBSD are /usr/rc.d/ and /usr/local/etc/rc.d/. The /usr/rc.d/ directory contains the system-provided scripts for the base system services, such as cron, sshd, syslogd, etc. The /usr/local/etc/rc.d/ directory contains the scripts for the additional services installed from ports or packages, such as apache, mysql, nginx, etc. These scripts follow the BSD rc.d framework, which allows for fine-grained control and customization of the startup process. The scripts are invoked by the main /etc/rc script, which sources the /etc/rc.conf file for configuration options

https://docs.freebsd.org/en/articles/rc-scripting/

The ports collection on FreeBSD is a package management system that allows users to install third-party software from source or binary packages. The ports collection is stored in the /usr/ports/ directory, which contains subdirectories for different categories of software, such as archivers, databases, editors, etc. Each subdirectory contains one or more ports, which are directories that contain the files needed to build and install the software. The /usr/ports/ directory can be updated with the portsnap command34

Binary packages are pre-compiled versions of the ports that can be installed with the pkg command. Binary packages are downloaded from the FreeBSD package repository,which is hosted at pkg.freebsd.org. The packages are installed in the /usr/local/ directory by default, and the information about the installed packages is stored in the /usr/local/pkg/ directory. The /usr/local/pkg/ directory contains files with the .db extension, which are SQLite databases that store the metadata of the packages. The pkg command can query and manipulate these databases56 References: 3: https://docs.freebsd.org/en/books/handbook/ports/  4: https://www.freebsd.org/ports/  5: https://docs.freebsd.org/en/books/handbook/pkgng-intro/  6: https://www.freebsd.org/cgi/man.cgi?query=pkg &sektion=8

The name of the NetBSD installation program is sysinst. It is the standard installer used by NetBSD for setting up the system on a new machine. The sysinst program guides users through the installation process, including disk partitioning, package selection, and system configuration45.

References:

• NetBSD Guide - Example installation
• NetBSD Guide - Installing NetBSD: Preliminary considerations and preparations

In FreeBSD, theunamecommand is used to display system information. The option-vspecifically displays the version of the running operating system. This information is critical for system administrators and users who need to know the exact version of the OS they are working with, particularly when troubleshooting, updating, or configuring the system for specific software requirements.

https://man.freebsd.org/cgi/man.cgi?query=uname &sektion=1&format=html

The -v or --version option of the uname command displays the version level of the operating system. This is a string that identifies the release date and patch level of the system. For example, on FreeBSD, the output would be something like:

FreeBSD 13.0-RELEASE-p4 #0: Tue Aug 24 07:12:34 UTC 2021

This indicates that the system is running FreeBSD 13.0, with the fourth patch applied, and that the kernel was built on August 24, 2021. The version level can be useful to determine the compatibility and security of the system, as well as to report bugs or issues.

The command locate.updatedb updates the database used by locate to find files. The locate command searches for files by name in a pre-built database of files and directories. The database is usually updated periodically by a cron job, but the locate.updatedb command can be used to manually update it. The command may require root privileges to run, depending on the system configuration. References:

• BSD Specialist Exam 702 Objectives, Topic 715: Basic Unix Skills, 715.4 Searching and Extracting Data from Files
• FreeBSD Handbook, Chapter 7: Finding and Installing Software, 7.2.3 Using locate(1) to Find Files Quickly

The command chown changes the ownership of a file or directory. The syntax is chown user:group file, where user is the new owner and group is the new group of the file. In this case, the superuser can grant the user bob write permission to the file by changing both the owner and the group of the file to bob. This way, bob will have the same permissions as the original owner, which is read and write. Alternatively, the superuser can also use the command chmod to change the permissions of the file without changing the ownership. For example, chmod g+w bobsfile will add write permission to the group, and chmod o+w bobsfile will add write permission to others. However, these commands will also affect other users who belong to the same group or are not the owner or the group of the file. References:

• FreeBSD Handbook: File and Directory Ownership
• FreeBSD Handbook: File and Directory Permissions
• Linux Professional Institute BSD Specialist: 702.1 Filesystem and Devices

The cron job syntax consists of five fields that specify the time and date of execution, followed by the command or script to run. The fields are: minute, hour, day of month, month, and day of week. Each field can have a specific value, a range, a list, a wildcard (), or a step value. The wildcard () means any possible value for that field. The option B sets the minute field to 0 and the hour field to *, which means the script will run at the 0th minute of every hour, regardless of the day, month, or weekday. This is equivalent to once per hour. The other options are either invalid syntax or do not match the desired frequency. For example, option A sets all fields to *, which means the script will run every minute of every hour of every day, month, and weekday. Option C sets the minute field to * and the hour field to 0, which means the script will run every minute of the 0th hour, or once per day at midnight. Option D has a typo (o instead of *) and option E sets the day of month field to o, which is not a valid value. References:

• crontab - FreeBSD crontab(5) Manual Page1
• Crontab Explained in Linux [With Examples] - Linux Handbook2