Free Practice Questions for CompTIA XK0-005 Exam

The docker exec ls command can be used to verify whether the built container has the app.go file in its root directory. This command will run the ls command inside the specified container and list the files and directories in its root directory. If the app.go file is present, it will be displayed in the output. The docker image inspect command will display information about an image, not a container, and it will not list the files inside the image. The docker container inspect command will display information about a container, not its files. The docker ps command is invalid, as ps does not accept a container name as an argument. References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 16: Virtualization and Cloud Technologies, page 499.

The command that will accomplish this task is sudo useradd -e 2021-09-30 Project_user. This command will create a new user account named Project_user with an expiration date of 2021-09-30. The -e option of useradd specifies the date on which the user account will be disabled in YYYY-MM-DD format.

The other options are not correct commands for creating a user account with an expiration date. The sudo useradd -c 2021-09-30 Project_user command will create a new user account named Project_user with a comment of 2021-09-30. The -c option of useradd specifies a comment or description for the user account, not an expiration date. The sudo modinfo -F 2021-09-30 Project_user command is invalid because modinfo is not a command for managing user accounts, but a command for displaying information about kernel modules. The -F option of modinfo specifies a field name to show, not an expiration date. The sudo useradd -m -d 2021-09-30 Project_user command will create a new user account named Project_user with a home directory of 2021-09-30. The -m option of useradd specifies that the home directory should be created if it does not exist, and the -d option specifies the home directory name, not an expiration date. References: useradd(8) - Linux manual page; modinfo(8) - Linux manual page

The df -h command can be used to identify the filesystem that is full. This command displays the disk usage of each mounted filesystem in a human-readable format, showing the total size, used space, available space, and percentage of each filesystem. The lsblk command displays information about block devices, not filesystems. The fdisk command can be used to manipulate partition tables, not check disk usage. The du -ah command displays the disk usage of each file and directory in a human-readable format, not the filesystems. References: [CompTIA Linux+ (XK0-005) Certification Study Guide], Chapter 14: Managing Disk Storage, page 454.

The administrator should add REQUIRES=mariadb.service to the HTTP server .service file to ensure that the database is available before the web application is started. This directive specifies that the HTTP server unit requires the MariaDB server unit to be started before it can run. If the MariaDB server unit fails to start or stops for any reason, the HTTP server unit will also fail or stop. This way, the dependency between the web application and the database is enforced by systemd.

The other options are not correct directives for accomplishing this task. TRIGGERS=mariadb.service is not a valid directive in systemd unit files. ONFAILURE=mariadb.service means that the HTTP server unit will start only if the MariaDB server unit fails, which is not what we want. WANTEDBY=mariadb.service means that the HTTP server unit will be started when the MariaDB server unit is enabled, but it does not imply a strong dependency or ordering relationship between them. References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 10: Managing Services with systemd; systemd.unit(5) - Linux manual page

The file id_rsa.pub will be moved to the remote servers for passwordless login. The id_rsa.pub file is the public authentication key that is generated by the ssh-keygen command. The public key can be copied to the remote servers by using the ssh-copy-id command or manually. The remote servers will use the public key to authenticate the user who has the corresponding private key (id_rsa). This will allow the user to log in without entering a password. The other options are incorrect because they are either private keys (id_rsa, id_dsa.pem, or id_ecdsa) or non-existent files (id_dsa.pem or id_ecdsa). References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 13: Managing Network Services, page 410.

The user has the wrong shell assigned to the account, which is causing the issue. The output 1 shows that the user’s shell is set to /bin/false, which is not a valid shell and will prevent the user from logging in. The output 2 shows that the user’s home directory has the correct permissions (drwxr-xr-x), and the output 3 shows that the user entered the correct password and was accepted by the SSH daemon, but the session was closed immediately due to the invalid shell. The other options are incorrect because they are not supported by the outputs. References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 13: Managing Network Services, page 413.

The issue is that the administrator did not set the default target to graphical.target. A target is a unit of systemd that groups together other units by a common purpose or state. The graphical.target is a target that starts the graphical user interface (GUI) along with other services. The administrator used the command systemct1 isolate graphical.target to switch to this target temporarily, but this does not change the default target that is activated at boot time. To make this change permanent, the administrator should have used the command systemct1 set-default graphical.target, which creates a symbolic link from /etc/systemd/system/default.target to /usr/lib/systemd/system/graphical.target.

The other options are not correct explanations for the issue. The administrator did reboot the server properly by using systemct1 reboot, which shuts down and restarts the system cleanly. The administrator did not need to set the default target to basic.target, which is a minimal target that only starts essential services. The administrator did not shut down the server improperly, which could have caused file system corruption or data loss, but not affect the default target. References: systemct1(1) - Linux manual page; How to Change Runlevels (targets) in SystemD

The RPM option -e should be used to remove software from the server. The rpm command is a tool for managing software packages on RPM-based Linux distributions. The -e option stands for erase and removes the specified package from the system. This is the correct option to use to accomplish the task. The other options are incorrect because they either do not exist (-s or -d) or do not remove software (-q stands for query and displays information about the package). References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 16: Managing Software, page 489.

The server’s firewall is preventing connections from being made, which is causing the connectivity issue. The output of iptables -L -n shows that the firewall is blocking all incoming traffic on port 22, which is the default port for SSH. The output of ssh -v user@104.21.75.76 shows that the connection is refused by the server. To resolve the issue, the administrator needs to allow port 22 on the firewall. The other options are incorrect because they are not supported by the outputs. The workstation has the correct IP settings, as shown by the output of ip addr show. The sshd service is enabled and running, as shown by the output of systemct1 status sshd. The server has the correct default gateway configuration, as shown by the output of ip route show. References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 13: Managing Network Services, pages 406-407.

The tool that is commonly used for creating CI/CD pipelines is Jenkins. Jenkins is an open-source automation server that enables continuous integration and continuous delivery (CI/CD) of software projects. Jenkins allows developers to build, test, and deploy code changes automatically and frequently using various plugins and integrations. Jenkins also supports distributed builds, parallel execution, pipelines as code, and real-time feedback. References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 19: Managing Source Code; Jenkins