A newly created container has been unable to start properly, and a Linux administrator is analyzing the cause of the failure. Which of the following will allow the administrator to determine the FIRST command that is executed inside the container right after it starts?

A. docker export

B. docker info

C. docker start

D. docker inspect

Which of the following tools is commonly used for creating CI/CD pipelines?

A. Chef

B. Puppet

C. Jenkins

D. Ansible

Which of the following actions are considered good security practices when hardening a Linux server? (Choose two.)

A. Renaming the root account to something else

B. Removing unnecessary packages

C. Changing the default shell to /bin/csh

D. Disabling public key authentication

E. Disabling the SSH root login possibility

F. Changing the permissions on the root filesystem to 600

A Linux administrator is installing a web server and needs to check whether web traffic has already been allowed through the firewall. Which of the following commands should the administrator use to accomplish this task?

A. firewalld query-service-http

B. firewall-cmd –check-service http

C. firewall-cmd –query-service http

D. firewalld –check-service http

A systems administrator is troubleshooting connectivity issues and trying to find out why a Linux server is not able to reach other servers on the same subnet it is connected to. When listing link parameters, the following is presented:
 
Based on the output above, which of following is the MOST probable cause of the issue?

A. The address ac:00:11:22:33:cd is not a valid Ethernet address.

B. The Ethernet broadcast address should be ac:00:11:22:33:ff instead.

C. The network interface eth0 is using an old kernel module.

D. The network interface cable is not connected to a switch.

A Linux administrator rebooted a server. Users then reported some of their files were missing. After doing some troubleshooting, the administrator found one of the filesystems was missing. The filesystem was not listed in /etc/fstab and might have been mounted manually by someone prior to reboot. Which of the following would prevent this issue from reoccurring in the future?

A. Sync the mount units.

B. Mount the filesystem manually.

C. Create a mount unit and enable it to be started at boot.

D. Remount all the missing filesystems.

An administrator is trying to diagnose a performance issue and is reviewing the following output:
 
System Properties:
CPU: 4 vCPU -
Memory: 40GB -
Disk maximum IOPS: 690 -
Disk maximum throughput: 44Mbps | 44000Kbps
Based on the above output, which of the following BEST describes the root cause?

A. The system has reached its maximum IOPS, causing the system to be slow.

B. The system has reached its maximum permitted throughput, therefore iowait is increasing.

C. The system is mostly idle, therefore the iowait is high.

D. The system has a partitioned disk, which causes the IOPS to be doubled.

A Linux administrator is creating a primary partition on the replacement hard drive for an application server. Which of the following commands should the administrator issue to verify the device name of this partition?

A. sudo fdisk /dev/sda

B. sudo fdisk -s /dev/sda

C. sudo fdisk -l

D. sudo fdisk -h

An administrator accidentally deleted the /boot/vmlinuz file and must resolve the issue before the server is rebooted. Which of the following commands should the administrator use to identify the correct version of this file?

A. rpm -qa | grep kernel; uname -a

B. yum -y update; shutdown -r now

C. cat /etc/centos-release; rpm -Uvh –nodeps

D. telinit 1; restorecon -Rv /boot

A systems administrator wants to back up the directory /data and all its contents to /backup/data on a remote server named remote. Which of the following commands will achieve the desired effect?

A. scp -p /data remote:/backup/data

B. ssh -i /remote:/backup/ /data

C. rsync -a /data remote:/backup/

D. cp -r /data /remote/backup/

A systems administrator installed a new software program on a Linux server. When the systems administrator tries to run the program, the following message appears on the screen.
 
Which of the following commands will allow the systems administrator to check whether the system supports virtualization?

A. dmidecode -s system-version

B. lscpu

C. sysctl -a

D. cat /sys/device/system/cpu/possible

A systems administrator is compiling a report containing information about processes that are listening on the network ports of a Linux server. Which of the following commands will allow the administrator to obtain the needed information?

A. ss -plnt

B. tcpdump -nL

C. netstat -pn

D. lsof -lt

A Linux administrator is scheduling a system job that runs a script to check available disk space every hour. The Linux administrator does not want users to be able to start the job. Given the following:
 
The Linux administrator attempts to start the timer service but receives the following error message:
 
Which of the following is MOST likely the reason the timer will not start?

A. The checkdiskspace.timer unit should be enabled via systemctl.

B. The timers.target should be reloaded to get the new configuration.

C. The checkdiskspace.timer should be configured to allow manual starts.

D. The checkdiskspace.timer should be started using the sudo command.

A Linux engineer needs to block an incoming connection from the IP address 2.2.2.2 to a secure shell server and ensure the originating IP address receives a response that a firewall is blocking the connection. Which of the following commands can be used to accomplish this task?

A. iptables -A INPUT -p tcp –dport ssh -s 2.2.2.2 -j DROP

B. iptables -A INPUT -p tcp –dport ssh -s 2.2.2.2 -j RETURN

C. iptables -A INPUT -p tcp –dport ssh -s 2.2.2.2 -j REJECT

D. iptables -A INPUT -p tcp –dport ssh -s 2.2.2.2 -j QUEUE

Due to performance issues on a server, a Linux administrator needs to terminate an unresponsive process. Which of the following commands should the administrator use to terminate the process immediately without waiting for a graceful shutdown?

A. kill -SIGKILL 5545

B. kill -SIGTERM 5545

C. kill -SIGHUP 5545

D. kill -SIGINT 5545

A cloud engineer needs to block the IP address 192.168.10.50 from accessing a Linux server. Which of the following commands will achieve this goal?

A. iptables -F INPUT -j 192.168.10.50 -m DROP

B. iptables -A INPUT -s 192.168.10.30 -j DROP

C. iptables -i INPUT –ipv4 192.168.10.50 -z DROP

D. iptables -j INPUT 192.168.10.50 -p DROP

A systems technician is configuring an application server to accept packets from a trusted source with the IP address 192.168.10.22. Which of the following commands will allow communication between the two servers?

A. iptables -L -s 192.168.10.22 -j ACCEPT

B. iptables -D INPUT -s 192.168.10.22 -j ACCEPT

C. iptables -A INPUT -s 192.168.10.22 -j ACCEPT

D. iptables -A OUTPUT -s 192.168.10.22 -j ACCEPT

SIMULATION -
Junior system administrator had trouble installing and running an Apache web server on a Linux server. You have been tasked with installing the Apache web server on the Linux server and resolving the issue that prevented the junior administrator from running Apache.
INSTRUCTIONS -
Install Apache and start the service. Verify that the Apache service is running with the defaults.
Typing “help” in the terminal will show a list of relevant event commands.
If at any time you would like to bring back the initial state of the simulation, please click the Reset All button.
 

A Linux engineer needs to download a ZIP file and wants to set the nice value to -10 for this new process. Which of the following commands will help to accomplish the task?

A. $ nice -v -10 wget https://foo.com/installation.zip

B. $ renice -v -10 wget https://foo.com/installation.zip

C. $ renice -10 wget https://foo.com/installation.zip

D. $ nice -10 wget https://foo.com/installation.zip

Users have been unable to reach www.comptia.org from a Linux server. A systems administrator is troubleshooting the issue and does the following:
 
Based on the information above, which of the following is causing the issue?

A. The name www.comptia.org does not point to a valid IP address.

B. The server 192.168.168.53 is unreachable.

C. No default route is set on the server.

D. The network interface eth0 is disconnected.

Users have reported that the interactive sessions were lost on a Linux server. A Linux administrator verifies the server was switched to rescue.target mode for maintenance. Which of the following commands will restore the server to its usual target?

A. telinit 0

B. systemctl reboot

C. systemctl get-default

D. systemctl emergency

A server is experiencing intermittent connection issues. Some connections to the Internet work as intended, but some fail as if there is no connectivity. The systems administrator inspects the server configuration:
 
Which of the following is MOST likely the cause of the issue?

A. An internal-only DNS server is configured.

B. The IP netmask is wrong for ens3.

C. Two default routes are configured.

D. The ARP table contains incorrect entries.

A developer needs to launch an Nginx image container, name it Web00l, and expose port 8080 externally while mapping to port 80 inside the container. Which of the following commands will accomplish this task?

A. docker exec -it -p 8080:80 –name Web001 nginx

B. docker load -it -p 8080:80 –name Web001 nginx

C. docker run -it -p 8080:80 –name Web001 nginx

D. docker pull -it -p 8080:80 –name Web001 nginx

A developer is trying to install an application remotely that requires a graphical interface for installation. The developer requested assistance to set up the necessary environment variables along with X11 forwarding in SSH. Which of the following environment variables must be set in remote shell in order to launch the graphical interface?

A. $RHOST

B. SETENV

C. $SHELL

D. $DISPLAY

A systems administrator is tasked with installing GRUB on the legacy MBR of the SATA hard drive. Which of the following commands will help the administrator accomplish this task?

A. grub-install /dev/hda

B. grub-install /dev/sda

C. grub-install /dev/sr0

D. grub-install /dev/hd0,0

A systems administrator is deploying three identical, cloud-based servers. The administrator is using the following code to complete the task:
 
Which of the following technologies is the administrator using?

A. Ansible

B. Puppet

C. Chef

D. Terraform

A Linux systems administrator receives a notification that one of the server’s filesystems is full. Which of the following commands would help the administrator to identify this filesystem?

A. lsblk

B. fdisk

C. df -h

D. du -ah

An administrator started a long-running process in the foreground that needs to continue without interruption. Which of the following keystrokes should the administrator use to continue running the process in the background?

A. bg

B. bg

C. jobs -1

D. bg &

A cloud engineer needs to check the link status of a network interface named eth1 in a Linux server. Which of the following commands can help to achieve the goal?

A. ifconfig hw eth1

B. netstat -r eth1

C. ss -ti eth1

D. ip link show eth1

A Linux administrator generated a list of users who have root-level command-line access to the Linux server to meet an audit requirement. The administrator analyzes the following /etc/passwd and /etc/sudoers files:
 
Which of the following users, in addition to the root user, should be listed in the audit report as having root-level command-line access? (Choose two.)

A. Carl

B. Lee

C. Mallory

D. Eve

E. Bob

F. Alice

The applications team is reporting issues when trying to access the web service hosted in a Linux system. The Linux systems administrator is reviewing the following outputs:
Output 1:
 
Output 2:
 
Which of the following statements best describe the root cause? (Choose two.)

A. The httpd service is currently started.

B. The httpd service is enabled to auto start at boot time, but it failed to start.

C. The httpd service was manually stopped.

D. The httpd service is not enabled to auto start at boot time.

E. The httpd service runs without problems.

F. The httpd service did not start during the last server reboot.

A Linux administrator was tasked with deleting all files and directories with names that are contained in the sobelete.txt file. Which of the following commands will accomplish this task?

A. xargs -f cat toDelete.txt -rm

B. rm -d -r -f toDelete.txt

C. cat toDelete.txt | rm -frd

D. cat toDelete.txt | xargs rm -rf

Joe, a user, is unable to log in to the Linux system. Given the following output:
 
Which of the following commands would resolve the issue?

A. usermod -s /bin/bash joe

B. pam_tally2 -u joe -r

C. passwd -u joe

D. chage -E 90 joe

A systems administrator is tasked with preventing logins from accounts other than root, while the file /etc/nologin exists. Which of the following PAM modules will accomplish this task?

A. pam_login.so

B. pam_access.so

C. pam_logindef.so

D. pam_nologin.so

A development team asks an engineer to guarantee the persistency of journal log files across system reboots. Which of the following commands would accomplish this task?

A. grep -i auto /etc/systemd/journald.conf && systemctl restart systemd-journald.service

B. cat /etc/systemd/journald.conf | awk ‘(print $1,$3)’

C. sed -i ‘s/auto/persistent/g’ /etc/systemd/journald.conf && sed -i ‘persistent/s/ˆ#//q’ /etc/systemd/journald.conf

D. journalctl –list-boots && systemctl restart systemd-journald.service

An administrator recently updated the BIND software package and would like to review the default configuration that shipped with this version. Which of the following files should the administrator review?

A. /etc/named.conf.rpmnew

B. /etc/named.conf.rpmsave

C. /etc/named.conf

D. /etc/bind/bind.conf

In which of the following filesystems are system logs commonly stored?

A. /var

B. /tmp

C. /etc

D. /opt

A Linux administrator was asked to run a container with the httpd server inside. This container should be exposed at port 443 of a Linux host machine while it internally listens on port 8443. Which of the following commands will accomplish this task?

A. podman run -d -p 443:8443 httpd

B. podman run -d -p 8443:443 httpd

C. podman run –d -e 443:8443 httpd

D. podman exec -p 8443:443 httpd

A Linux system is getting an error indicating the root filesystem is full. Which of the following commands should be used by the systems administrator to resolve this issue? (Choose three.)

A. df -h /

B. fdisk -1 /dev/sdb

C. growpart /dev/mapper/rootvg-rootlv

D. pvcreate /dev/sdb

E. lvresize –L +10G -r /dev/mapper/rootvg-rootlv

F. lsblk /dev/sda

G. parted -l /dev/mapper/rootvg-rootlv

H. vgextend /dev/rootvg /dev/sdb

A Linux administrator has logged in to a server for the first time and needs to know which services are allowed through the firewall. Which of the following options will return the results for which the administrator is looking?

A. firewall-cmd –get-services

B. firewall-cmd –check-config

C. firewall-cmd –list-services

D. systemctl status firewalld

A systems administrator is tasked with setting up key-based SSH authentication. In which of the following locations should the administrator place the public keys for the server?

A. ~/.sshd/authkeys

B. ~/.ssh/keys

C. ~/.ssh/authorized_keys

D. ~/.ssh/keyauth

A DevOps engineer needs to download a Git repository from https://git.company.com/admin/project.git. Which of the following commands will achieve this goal?

A. git clone https://git.company.com/admin/project.git

B. git checkout https://git.company.com/admin/project.git

C. git pull https://git.company.com/admin/project.git

D. git branch https://git.company.com/admin/project.git

A Linux administrator has installed a web server, a database server, and a web application on a server. The web application should be active in order to render the web pages. After the administrator restarts the server, the website displays the following message in the browser: Error establishing a database connection. The Linux administrator reviews the following relevant output from the systemd init files:
 
The administrator needs to ensure that the database is available before the web application is started. Which of the following should the administrator add to the HTTP server .service file to accomplish this task?

A. TRIGGERS=mariadb.service

B. ONFAILURE=mariadb.service

C. WANTEDBY=mariadb.service

D. REQUIRES=mariadb.service

A cloud engineer needs to change the secure remote login port from 22 to 49000. Which of the following files should the engineer modify to change the port number to the desired value?

A. /etc/host.conf

B. /etc/hostname

C. /etc/services

D. /etc/ssh/sshd_config

A Linux engineer receives reports that files created within a certain group are being modified by users who are not group members. The engineer wants to reconfigure the server so that only file owners and group members can modify new files by default. Which of the following commands would accomplish this task?

A. chmod 775

B. umask. 002

C. chattr -Rv

D. chown -cf

A junior administrator is setting up a new Linux server that is intended to be used as a router at a remote site. Which of the following parameters will accomplish this goal?

A.

B.

C.

D.

An administrator runs ping comptia. org. The result of the command is:
ping: comptia.org: Name or service not known
Which of the following files should the administrator verify?

A. /etc/ethers

B. /etc/services

C. /etc/resolv.conf

D. /etc/sysctl.conf

After installing some RPM packages, a systems administrator discovers the last package that was installed was not needed. Which of the following commands can be used to remove the package?

A. dnf remove packagename

B. apt-get remove packagename

C. rpm -i packagename

D. apt remove packagename

An administrator would like to measure possible packet loss between a workstation and a remote web application that is running on port 443. Which of the following would be the best command for the administrator to use to display this information?

A. ping -c 50

B. tcpdump -p 443

C. mtr -T -P 443

D. traceroute -p 443

A new disk was presented to a server as /dev/sdd. The systems administrator needs to check if a partition table is on that disk. Which of the following commands can show this information?

A. lsscsi

B. fdisk

C. blkid

D. partprobe