Red Hat Certified System Administrator RHCSA Simulator #1

Question 1 of 60

1. Question

A system administrator wants to view the contents of a text file named “servers.txt”. Which of the following commands will display the contents of this file directly on the shell prompt?

```
cat servers.txt
```
```
cp servers.txt
```
```
chmod servers.txt
```
```
chown servers.txt
```

Question 2 of 60

2. Question

An administrator wants to issue a single command to change the directory to “/var/log” and then list the contents of that directory. Which of the following commands accomplishes this?

```
cd /var/log && ls
```
```
mv /var/log
```
```
ls /var/log | cd
```
```
rm /var/log
```

Question 3 of 60

3. Question

A system administrator wants to execute the find command to search for files named “error.log” in the “/logs” directory and direct both standard output and standard error to a file named “results.txt”. Which of the following commands will achieve this objective?

find /logs -name error.log 2> results.txt

find /logs -name error.log > results.txt

find /logs -name error.log > results.txt 2>&1

find /logs -name error.log | results.txt

Question 4 of 60

4. Question

An administrator wants to concatenate the contents of two files “file1.txt” and “file2.txt”, then pipe the combined output to the grep command to search for the word “error”. The result should be appended to a file named “output.txt”. Which of the following commands will fulfill this requirement?

cat file1.txt file2.txt | grep error >> output.txt

cat file1.txt + file2.txt | grep error >> output.txt

cat file1.txt file2.txt > grep error >> output.txt

cat file1.txt file2.txt && grep error >> output.txt

Question 5 of 60

5. Question

A system administrator needs to search for lines in a file named “logs.txt” that start with the word “ERROR” followed by a date in the format “YYYY-MM-DD”. Which of the following grep commands can achieve this?

grep '^ERROR [0-9]{4}-[0-9]{2}-[0-9]{2}' logs.txt

grep 'ERROR* [0-9]{4}-[0-9]{2}-[0-9]{2}' logs.txt

grep '^ERROR.*[0-9]-[0-9]-[0-9]' logs.txt

```
grep 'ERROR.*' logs.txt
```

Question 6 of 60

6. Question

You need to extract lines from a file named users.txt that start with a capital letter followed by exactly two lowercase letters. Which grep command would accomplish this?

```
grep '^[A-Z][a-z][a-z]$' users.txt
```
```
grep '^[A-Z][a-z]{2}$' users.txt
```
```
grep '^[A-Z][a-z]{2}' users.txt
```
```
rep '^[A-Z]{3}' users.txt
```

Question 7 of 60

7. Question

You’re writing a shell script that should execute a block of code only if the variable $count has a value greater than 10. Which of the following code snippets correctly implements this logic?



if [$count > 10]

then

   # block of code

fi



if [ $count -gt 10 ]

then

   # block of code

fi



if $count > 10

then

   # block of code

fi



if test $count = 10

then

   # block of code

fi

Question 8 of 60

8. Question

You’ve received a shell script that uses conditional statements. In one of the conditions, the script checks if a file named data.txt exists. Which of the following conditions correctly checks for the existence of the file?



if [ -e data.txt ]

then

   # block of code

fi



if test data.txt

then

   # block of code

fi



if [ data.txt == exists ]

then

   # block of code

fi



if [ -exists data.txt ]

then

   # block of code

fi

Question 9 of 60

9. Question

You are writing a shell script that processes a list of filenames provided as arguments to the script. You want to print each filename with its line number. Which of the following code snippets correctly implements this logic?



for filename in $*

do

  echo "$filename"

done



counter=1

for filename in "$@"

do

  echo "$counter. $filename"

  ((counter++))

done



for filename in $ARGS

do

  echo "$filename"

done



for $filename in $@

do

  echo "$filename"

done

Question 10 of 60

10. Question

You have a file named servers.txt that contains a list of server names, one on each line. You need to write a script that pings each server and checks if it’s online. Which of the following code snippets will correctly process each server in the file?



for server in servers.txt

do

  ping -c 1 $server

done



for server in $(cat servers.txt)

do

  ping -c 1 "$server"

done



while read server; do

  ping -c 1 $server

done < servers.txt



for server in $(echo servers.txt)

do

  ping -c 1 "$server"

done

Question 11 of 60

11. Question

You are tasked with writing a script that accepts two arguments: a filename and a search string. The script should search for the string within the file and display the number of occurrences. Given the following command execution: ./search.sh data.txt “Hello”, which code snippet correctly processes these inputs?



filename=$1

search_string=$2

grep -c "$filename" "$search_string"



filename=$2

search_string=$1

grep -c "$filename" "$search_string"



filename=$1

search_string=$2

grep -c "$search_string" "$filename"



filename=$0

search_string=$1

grep -c "$search_string" "$filename"

Question 12 of 60

12. Question

You have a script that needs to concatenate its first two arguments with a hyphen in between and print the result. If the script is invoked as ./concat.sh Red Hat, what code snippet produces the output Red-Hat?

```
echo "$2-$1"
```
```
echo "$1+$2"
```
```
echo "$1-$2"
```
```
echo "$0-$1"
```

Question 13 of 60

13. Question

You are troubleshooting a server that is experiencing issues. You want to boot the system into a single-user mode for maintenance without network services. Which command should you use at the bootloader to achieve this?

```
linux 16 single
```
```
linux 16 rescue
```
```
linux 16 emergency
```
```
linux 16 maintenance
```

Question 14 of 60

14. Question

After performing some hardware changes on a system, you want to shut it down immediately without saving any current work or sending any notifications to users. Which of the following commands would you use?

```
shutdown -h now
```
```
shutdown -r now
```
```
halt
```
```
reboot
```

Question 15 of 60

15. Question

You are tasked with starting a Red Hat system in a state suitable for administrative tasks, without any network interfaces being activated. Which target should you boot the system into?

```
graphical.target
```
```
multi-user.target
```
```
network.target
```
```
rescue.target
```

Question 16 of 60

16. Question

You have been instructed to start a Red Hat system in a graphical mode without multi-user support, suitable for one person at a time. Which systemd target should you use for this purpose?

```
emergency.target
```
```
isolated.target
```
```
graphical.target
```
```
single-user.target
```

Question 17 of 60

17. Question

While booting a Red Hat system, you need to interrupt the boot process to reset the root password. Which key should you press during the GRUB 2 boot loader stage to achieve this?

F2
Ctrl + C
Escape (Esc)
Enter

Question 18 of 60

18. Question

You’ve successfully interrupted the boot process using the GRUB 2 bootloader on a Red Hat system. You want to modify the boot parameters to initiate a recovery process. Which line should you navigate to and edit in the GRUB menu?

```
linux16
```
```
initrd16
```
```
set root
```
```
menuentry
```

Question 19 of 60

19. Question

An administrator is performing an audit of the system’s hard drives. She wants to list the partitions on the disk /dev/sda which is an MBR disk. Which command will provide this information?

```
lsblk /dev/sda
```
```
fdisk -l
```
```
gdisk -l /dev/sda
```
```
parted /dev/sda print
```

Question 20 of 60

20. Question

A system administrator wants to create a new GPT partition on the disk /dev/sdb. Which tool would be most appropriate for this task?

```
cfdisk /dev/sdb
```
```
fdisk /dev/sdb
```
```
gdisk /dev/sdb
```
```
mkpart /dev/sdb
```

Question 21 of 60

21. Question

An administrator wants to create a physical volume on /dev/sdc1 for use in an LVM configuration. Which command should she use to accomplish this?

```
lvcreate /dev/sdc1
```
```
pvcreate /dev/sdc1
```
```
fdisk /dev/sdc1
```
```
vgcreate /dev/sdc1
```

Question 22 of 60

22. Question

After reconfiguring an LVM, the administrator needs to remove the physical volume /dev/sdd1 from the system. Before doing so, she must ensure there are no active volume groups on it. Which command should she use to remove the physical volume?

```
vgremove /dev/sdd1
```
```
lvremove /dev/sdd1
```
```
fdisk /dev/sdd1
```
```
pvremove /dev/sdd1
```

Question 23 of 60

23. Question

John, a system administrator, has recently added two new physical volumes, /dev/sdb1 and /dev/sdc1, to a system. He wants to include them in an existing volume group named “vg_data”. Which command should he use?

```
vgcreate vg_data /dev/sdb1 /dev/sdc1
```
```
vgextend vg_data /dev/sdb1 /dev/sdc1
```
```
pvadd vg_data /dev/sdb1 /dev/sdc1
```
```
lvextend vg_data /dev/sdb1 /dev/sdc1
```

Question 24 of 60

24. Question

A system administrator is monitoring the physical volumes in the “vg_web” volume group. Before adding new physical volumes, she needs to know which ones are currently assigned to “vg_web”. Which command will display this information?

```
vgdisplay -v vg_web
```
```
pvscan
```
```
lvdisplay vg_web
```
```
vgscan
```

Question 25 of 60

25. Question

You are working on a Linux system and need to format a newly attached disk (/dev/sdb1) with the xfs file system. Which command would you use to accomplish this?

```
mkfs.vfat /dev/sdb1
```
```
mkfs.ext4 /dev/sdb1
```
```
mkfs.xfs /dev/sdb1
```
```
xfs_mkfs /dev/sdb1
```

Question 26 of 60

26. Question

You have mounted an ext4 file system from /dev/sdc1 to the /mnt/data directory. However, you now need to perform maintenance on this partition and must ensure that it’s no longer in use. Which command should you use to safely unmount this file system?

```
umount /mnt/data
```
```
mount -u /mnt/data
```
```
eject /mnt/data
```
```
fdisk -u /mnt/data
```

Question 27 of 60

27. Question

You are tasked with mounting an NFS share from the server 192.168.1.10 with the shared directory /exports/data. You want to mount this share to the local directory /mnt/nfsdata. Which command will correctly perform this action?

mount 192.168.1.10:/exports/data /mnt/nfsdata

nfs-mount /mnt/nfsdata 192.168.1.10:/exports/data

mount -t nfs /mnt/nfsdata 192.168.1.10:/exports/data

mount -t nfs 192.168.1.10:/exports/data /mnt/nfsdata

Question 28 of 60

28. Question

Your system is currently accessing files from an NFS share, but you need to perform some maintenance on the local directory /mnt/nfsdocs where the NFS share is mounted. Which command should you use to safely unmount this NFS share?

```
unmount /mnt/nfsdocs
```
```
mount -u nfs /mnt/nfsdocs
```
```
umount /mnt/nfsdocs
```
```
nfs-umount /mnt/nfsdocs
```

Question 29 of 60

29. Question

You have been given a task to set up autofs for the users in your organization. Each user has a home directory on the NFS server at 192.168.2.5 under /export/users. You need to ensure that when a user accesses /home/username on the local machine, their home directory from the NFS server is automatically mounted. Where should you define this mount in the autofs configuration?

```
In /etc/auto.master
```
```
In /etc/auto.misc
```
```
In /etc/auto.home
```
```
In /etc/nfs/auto.users
```

Question 30 of 60

30. Question

After setting up autofs for your team, a user reports they are unable to access their NFS-mounted home directory. Which command should you use to restart the autofs service and apply any changes made to the configuration files?

```
service autofs start
```
```
systemctl start autofs
```
```
systemctl restart autofs
```
```
service nfs restart
```

Question 31 of 60

31. Question

John, a system administrator, needs to run a script named backup.sh from the /opt/scripts/ directory every Monday at 3:00 AM. Which of the following entries should he add to the crontab to achieve this?

```
0 3 * * 1 /opt/scripts/backup.sh
```
```
3 0 * * 1 /opt/scripts/backup.sh
```
```
0 3 * * 7 /opt/scripts/backup.sh
```
```
at 3:00 /opt/scripts/backup.sh
```

Question 32 of 60

32. Question

Alice wants to run a one-time task tomorrow at 5:30 PM. She wants to execute the script /home/alice/maintenance.sh. Which of the following commands will allow her to schedule the task?

at 5:30 PM tomorrow -f /home/alice/maintenance.sh

cron 17:30 tomorrow -f /home/alice/maintenance.sh

at -f /home/alice/maintenance.sh 5:30 PM

at now + 1 day 5:30 PM -f /home/alice/maintenance.sh

Question 33 of 60

33. Question

Amy, a system administrator, wants to ensure that the Apache HTTP Server starts automatically whenever the system boots. Which command should she use to enable the service to start on boot for a system using systemd?

```
systemctl enable apache2
```
```
systemctl start apache2
```
```
chkconfig apache2 on
```
```
service apache2 restart
```

Question 34 of 60

34. Question

Linda has been tasked to convert a server into a lightweight web server. To save resources, she decides that the server should only boot into a mode with essential services and without any network. Which target should she set the system to boot into by default?

```
emergency.target
```
```
rescue.target
```
```
multi-user.target
```
```
network.target
```

Question 35 of 60

35. Question

You are setting up a system to synchronize its clock with a remote NTP server at ntp.example.com. Which of the following commands would you use to ensure the system’s clock stays synchronized with this server?

```
chronyc set-server ntp.example.com
```
```
chronyc add server ntp.example.com
```
```
timedatectl set-ntp ntp.example.com
```

echo "server ntp.example.com" >> /etc/chrony/chrony.conf

Question 36 of 60

36. Question

A system administrator notices that the server’s time is not synchronizing with the NTP servers specified in the /etc/chrony/chrony.conf file. Which of the following commands would be best to check the synchronization status?

```
chronyc sync
```
```
chronyc tracking
```
```
timedatectl status
```
```
chronyc servers
```

Question 37 of 60

37. Question

Anna is configuring a RHEL 8 server’s networking and needs to assign the IPv4 address 192.168.1.10/24 to the network interface named “eth0”. Which nmcli command should she use to accomplish this?

nmcli connection modify eth0 ipv4.address 192.168.1.10/24

nmcli connection set eth0 ip4 192.168.1.10/24

nmcli device set eth0 ipv4 192.168.1.10/24

```
nmcli modify eth0 address 192.168.1.10
```

Question 38 of 60

38. Question

Brian is asked to configure an IPv6 address on a network interface named “ens3” without disrupting any current configurations. He needs to add the address “2001:0db8:85a3::8a2e:0370:7334/64”. Which command should he use?

ip addr add 2001:0db8:85a3::8a2e:0370:7334/64 dev ens3

nmcli connection modify ens3 ipv6.addresses 2001:0db8:85a3::8a2e:0370:7334/64

ifconfig ens3 add 2001:0db8:85a3::8a2e:0370:7334/64

nmcli device modify ens3 add ipv6 2001:0db8:85a3::8a2e:0370:7334/64

Question 39 of 60

39. Question

Jacob is working on a RHEL 8 server and wants to set the system’s static hostname to “webserver01.company.local”. Which command should he use to accomplish this task?

```
hostnamectl set-hostname webserver01
```

nmcli general hostname webserver01.company.local

```
hostname webserver01.company.local
```

hostnamectl set-hostname webserver01.company.local

Question 40 of 60

40. Question

Sophie wants to ensure that the system will resolve the hostname “backupserver.company.local” to the IP address “10.0.0.5” without using an external DNS server. Where should she add this configuration?

```
In the /etc/hostname file
```
```
In the /etc/resolv.conf file
```
```
In the /etc/hosts file
```
```
In the /etc/network/interfaces file
```

Question 41 of 60

41. Question

Emily wants to ensure that the SSH service starts automatically when her RHEL 8 system boots up. Which command should she use to achieve this?

```
systemctl enable ssh
```
```
service sshd auto-start
```
```
systemctl start sshd
```
```
systemctl enable sshd
```

Question 42 of 60

42. Question

John is setting up a web server on RHEL 8 and wants to ensure that the Apache HTTP service, httpd, starts every time the system boots. However, he does not want to start the service immediately. Which command should John execute?

```
systemctl start httpd
```
```
systemctl enable httpd
```
```
chkconfig httpd on
```
```
httpd --auto-start
```

Question 43 of 60

43. Question

You have been given a task to create a new local user account named “jdoe” on a Red Hat system, but without creating a home directory for this user. Which of the following commands accomplishes this task?

```
useradd -h jdoe
```
```
useradd jdoe
```
```
useradd -M jdoe
```
```
usermod -c jdoe
```

Question 44 of 60

44. Question

After a recent audit, you’ve been instructed to delete the local user account “tempuser” from a Red Hat system but keep the user’s home directory intact. Which of the following commands will you use to achieve this?

```
userdel tempuser
```
```
userdel -r tempuser
```
```
usermod -d /dev/null tempuser
```
```
rmuser tempuser
```

Question 45 of 60

45. Question

As a system administrator, you’ve been given a directive to change the password for the user “james” without any user interaction (i.e., prompts). Which command would allow you to set a new password for this user directly from a hashed value?

```
passwd james
```
```
passwd -d james
```
```
chage -M 30 james
```
```
echo 'james:hashed_value' | chpasswd -e
```

Question 46 of 60

46. Question

In order to ensure strong password policies, you are required to ensure that the password for the user “linda” must be changed every 45 days. Which command accomplishes this requirement?

```
passwd -x 45 linda
```
```
chage -M 45 linda
```
```
usermod -e 45 linda
```
```
passwd -n 45 linda
```

Question 47 of 60

47. Question

A new system administrator named “alex” has recently joined your team. You’ve been tasked with giving “alex” temporary sudo access to run all commands as root, but without needing to know the root password. Which of the following entries in the /etc/sudoers file would achieve this?

```
alex ALL = PASSWD: ALL
```
```
alex ALL = NOPASSWD: ALL
```
```
alex ALL = (root) ALL
```
```
alex ALL = ALL: NOPASSWD
```

Question 48 of 60

48. Question

You are configuring a server and want to ensure that the user “patricia” can run the /sbin/ifconfig and /sbin/shutdown commands as root without being prompted for a password. Which entry in the /etc/sudoers file would provide the necessary access?

patricia ALL=(ALL) /sbin/ifconfig, /sbin/shutdown

patricia ALL=(root) NOPASSWD: /sbin/ifconfig, /sbin/shutdown

patricia ALL=/sbin/ifconfig NOPASSWD: /sbin/shutdown

patricia root= NOPASSWD: /sbin/ifconfig, /sbin/shutdown

Question 49 of 60

49. Question

You’ve set up a web server on your Red Hat system and want to allow incoming HTTP traffic. Using the firewall-cmd tool, which command will permanently open the HTTP service on the default zone?

firewall-cmd --add-service=http --permanent

firewall-cmd --zone=public --add-service=http

firewall-cmd --open-service=http --permanent

```
firewall-cmd --service=http --enable
```

Question 50 of 60

50. Question

You need to list all the active zones along with their configurations on your Red Hat system. Which firewall-cmd command will accomplish this?

```
firewall-cmd --list-all-zones
```
```
firewall-cmd --get-active-zones
```
```
firewall-cmd --show-zones
```
```
firewall-cmd --zones-info
```

Question 51 of 60

51. Question

You are tasked with ensuring that all new files created in the /data directory should be readable and writable by the group. Which command would you use to set the default permissions for new files in this directory?

```
chmod 760 /data
```
```
setfacl -m d:u::rw,g::rw,o::- /data
```
```
chmod g+s /data
```
```
umask 0027 /data
```

Question 52 of 60

52. Question

Alex wants to ensure that any new files he creates in his home directory are not executable by default, but are readable and writable by him. Which umask value should he set in his profile?

```
0077
```
```
0022
```
```
0002
```
```
0111
```

Question 53 of 60

53. Question

James is attempting to set up key-based authentication for his SSH server. He has generated a public and private key pair on his client machine. Where should he place the public key on the server to allow key-based authentication?

```
In /home/james/.ssh/authorized_keys
```
```
In /home/james/.ssh/id_rsa.pub
```
```
In /etc/ssh/ssh_host_rsa_key.pub
```
```
In /etc/ssh/ssh_known_hosts
```

Question 54 of 60

54. Question

Anna wishes to implement an SSH key-based authentication system for her servers, but she wants to add an extra layer of security. Which of the following actions would provide additional security to her private key?

Store the private key on a shared network drive
Remove the passphrase from the private key
Use a passphrase when generating the private key
Change the permissions of the private key to 777

Question 55 of 60

55. Question

Alice is working on building a custom container image. She has prepared a Containerfile in the current directory. Which command will help her build the container image with the name “my_custom_image”?

podman container build -t my_custom_image .

podman build -f Containerfile my_custom_image

```
podman build -t my_custom_image .
```

skopeo build Containerfile my_custom_image

Question 56 of 60

56. Question

Michael is tasked with building a container image using a Containerfile located in the /app/container_build directory. The Containerfile has been named “myContainerFile”. Which command will help Michael build an image named “app_image”?

podman build -f /app/container_build/myContainerFile -t app_image /app/container_build

skopeo build -t app_image /app/container_build/myContainerFile

podman -t app_image build /app/container_build/myContainerFile

podman build /app/container_build -n myContainerFile -t app_image

Question 57 of 60

57. Question

John has just pulled a container image named “webserver” from a registry. He wants to run this image as a container in detached mode (background). Which command should he use?

```
podman start -d webserver
```
```
podman run -d webserve
```
```
podman execute -d webserver
```
```
skopeo run webserver
```

Question 58 of 60

58. Question

Rachel needs to list all running containers on her system. Which command will provide her with the desired information?

```
podman list
```
```
podman ps
```
```
skopeo list containers
```
```
podman show containers
```

Question 59 of 60

59. Question

Alex has just set up a Redis container and wants to ensure that it starts automatically when the system boots. Which of the following commands should Alex use to generate a systemd service unit file for the Redis container?

podman generate systemd --name redis-container

```
systemctl enable redis-container
```
```
podman start redis-container --systemd
```
```
podman systemd generate redis-container
```

Question 60 of 60

60. Question

After generating the systemd service unit file for her MariaDB container named “mariadb-container”, Lisa wants to ensure that it’s enabled and will start on system boot. Where should she place the generated service unit file and which command should she use afterward?

Place in /usr/lib/systemd/system/ and run systemctl enable mariadb-container
Place in /etc/systemd/system/ and run systemctl start mariadb-container
Place in /etc/podman/systemd/ and run systemctl enable mariadb-container.service
Place in /etc/systemd/system/ and run systemctl enable mariadb-container.service