Test your basic knowledge |

RHCSA

Subjects : certifications, it-skills, rhcsa

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What option is used with both the fdisk and parted commands to display the current partition tables?
The SMTP service runs on TCP port 110.
The virsh command is used to manage virtual guests.
chkconfig xinetd --list
The print option is used with both the fdisk and parted commands to display the current partition tables.

2. What is the /etc/hosts file used for?

3. What are the three different types of RAID described in this chapter?
Use the resize2fs command to grow a file system.
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.

4. What port does the SMTP service run on?
SELinux Booleans provide restrictions to different aspects of a service.
The SMTP service runs on TCP port 110.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
By default - Squid runs on port 3128.

5. What command can you use to view the current ACL on a file?
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
Network installations can be performed using the HTTP - FTP - and NFS protocols.
The firewall rule is inserted into the fifth line of the iptables rules and opens up TCP port 80 (for the HTTP service) on the firewall to allow incoming connections.
getfacl

6. What is the format of the /etc/shadow file?
The smbpasswd command is used to create Samba users.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
A gateway is used as an entry and exit point for a subnet on a network. To contact hosts outside your subnet - you need to pass through a gateway.

7. SSH does...
A virtual host is a way of hosting multiple sites using a single IP address.
support TCP Wrappers
The firewall rule is inserted into the fifth line of the iptables rules and opens up TCP port 80 (for the HTTP service) on the firewall to allow incoming connections.
createrepo

8. Place all files you want added to a _______________ during creation.

9. What two ports should be opened on the firewall for the FTP server to function properly?
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
You must open TCP ports 20 and 21 for the FTP server to function properly.
kickstart installations to work

10. What three protocols can you use to perform network installations?
Network installations can be performed using the HTTP - FTP - and NFS protocols.
rpcbind service
You can use the -q option to query an installed package. Combining grep and the -qa options - you can search among all installed packages on the system.
chkconfig sshd off

11. The firewall service is...
useradd -c "Jr Admin" George
The htpasswd command can be used to password-protect a web page.
enabled by default
chkconfig—list

12. What two commands are used for package management?
chcon
The user_list file can be used to limit which users have access to the FTP server.
chkconfig—list
The yum and rpm commands are used for package management.

13. What is the point of using SELinux?
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.
SELinux provides enhanced granular security for the Linux operating system.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
you have access to the correct packages or repositories.

14. Do you need to write changes to the disk when using the parted command? What about fdisk?
This command sets the eth1 interface to have a static IP address of 172.168.1.100 with a netmask of 255.255.255.0.
export one or all resources
When you exit the parted utility - all your changes are automatically written to disk. With the fdisk command - you need to manually write your changes to disk for them to take effect.
rpcbind service

15. What command can be used to easily list all the options in the FTP main config file?
serve both files and printers to users
The two main config files are master.cf and main.cf.
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
choose which mode you'd like it to operate in

16. What command can you use to view NFS statistics?
The four types of DNS servers are master - slave - caching-only - and forwarding.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
The nfsstat command can be used to view NFS statistics.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.

17. What is the main config file for the DHCP service?
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.
The htpasswd command can be used to password-protect a web page.
service sshd statuts
The mount command lists all currently mounted file systems.

18. The ____________ is available for each share.
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
browseable option
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
Use the resize2fs command to grow a file system.

19. What is the xinetd service used for?
You must ensure that the /boot/grub/grub.conf file has the new entry for your newly updated kernel to be able to boot into it.
You can use the remove or erase options with yum to remove a package.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
You add your action to the end of the /home/user01/.bashrc file.

20. What command can you use to create a password-protected page?
The dig - host - and ping commands can be used to test DNS server functionality.
The htpasswd command can be used to password-protect a web page.
SSH is used for secure remote management of Linux systems.
The rndc utility provides a method for managing the DNS server remotely and securely.

21. What command can you use to validate the syntax of the Apache config file?
Public/private key authentication provides an additional layer of security because you need the correct key instead of just knowing someone's password. Passwords combined with public/private keys take the security one additional step.
The SMTP service runs on TCP port 110.
service httpd configtest
A swap is scratch space on your file system used as virtual memory. A swap can be created as a partition or a device file.

22. How can virtual hosts be used?
If you are a hosting company or want to run multiple websites/applications from a single IP address - you can use virtual hosts to accomplish this.
Using the chcon command - you can change the context of a file to work with Apache.
This is actually a trick question because the answer could go either way. In this chapter - we discussed only software RAID setups - in which case the answer is no. If - however - you were using a hardware RAID 5 - the answer would be yes.
The TFTP server uses UDP port 69.

23. What critical step must you take after updating the kernel to a newer version?
The user_list file can be used to limit which users have access to the FTP server.
You must ensure that the /boot/grub/grub.conf file has the new entry for your newly updated kernel to be able to boot into it.
Stage 1: During this stage - the primary bootloader is read into memory by the BIOS from the MBR. Stage 1.5: During this stage - the bootloader is read into memory by the stage 1 bootloader (only if necessary). Stage 2: During this stage - the bootlo
load balancing and redundancy benefits

24. What benefit does a web proxy provide to your network?
load balancing and redundancy benefits
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
export one or all resources

25. What three commands can you use to help verify that the DNS server is functioning properly?
createrepo
defining a %pre section although it is rarely used
The dig - host - and ping commands can be used to test DNS server functionality.
export one or all resources

26. Samba servers can...
Sendmail
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
serve both files and printers to users
Use the yum groupinstall command to install multiple packages in a single group at once.

27. What command do you use to change the permissions on a file or directory - To change ownership?
getfacl
The user_list file can be used to limit which users have access to the FTP server.
The chmod command is used to change the permissions of files and directories. The chown command is used to change the ownership of files and directories.
chkconfig xinetd --list

28. What command is used to create a user for Samba?
You can use the remove or erase options with yum to remove a package.
The smbpasswd command is used to create Samba users.
Enforcing during installation
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George

29. How would you install a group of packages all at a single time?
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
Use the yum groupinstall command to install multiple packages in a single group at once.
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.
schedule one-time-only jobs

30. What is the benefit of using public/private key authentication?

31. What port must be opened on the firewall for DNS?
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
Use the resize2fs command to grow a file system.
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
DNS uses port 53.

32. Which log file is used to keep track of policy violations?
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
The /var/log/audit/audit.log file contains all policy violations.
Use the route command with the add option to create a static route.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.

33. What file is used to maintain custom parameters for the kernel during system boot?
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
Physical volumes - volume groups - and logical volumes.
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
service sshd statuts

34. The default SMTP service has been changed from _________ to Postfix in Red Hat Enterprise Linux 6.
The three utilities are: route - ping - and nslookup.
service httpd configtest
Sendmail
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.

35. What are the three modes in which the rpm command can operate?
The tcpdump command is used to monitor network connections on different interfaces.
defining a %pre section although it is rarely used
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
The rpm command can operate in install - query - or verify modes.

36. What command can you use to manage system services?
The service command is used to start - stop - and manage system services.
chcon
entering rescue mode and repairing the problem.
service httpd configtest

37. What happens to jobs that are scheduled to run while the system is off?
Sendmail
service httpd configtest
When the system starts up again - the cron service will run any jobs that were missed while the system was off. On Red Hat Enterprise Linux 5 - the anacron service handles this functionality.
Public/private key authentication provides an additional layer of security because you need the correct key instead of just knowing someone's password. Passwords combined with public/private keys take the security one additional step.

38. The portmap service was replaced by the ______________ in Red Hat Enterprise Linux 6.
rpcbind service
Using the chcon command - you can change the context of a file to work with Apache.
Use the top command to view CPU and memory usage.
Use the ps command to view processes and their CPU usage.

39. What is the /var/lib/nfs/etab file used for?
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514
The /var/lib/nfs/etab file is used to keep track of currently exported resources.

40. Which file contains all messages generated during installation that can be used for troubleshooting if the need arises?
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
The install.log.syslog file contains messages that are generated during the installation. If you run into trouble during the installation - this is a good place to start.
The firewall rule is inserted into the fifth line of the iptables rules and opens up TCP port 80 (for the HTTP service) on the firewall to allow incoming connections.
getsebool

41. What is the superblock used for?
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
The du and df commands are used to view available space on the system.
chkconfig sshd off

42. The at command is used to ____________. The cron service handles reoccurring system jobs.
The anonymous_enable=YES option in the main config file allows anonymous uploads.
Physical volumes - volume groups - and logical volumes.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
schedule one-time-only jobs

43. What are the side effects of shrinking a volume group or logical volume?
support for TCP Wrappers
Using the chcon command - you can change the context of a file to work with Apache.
If you shrink a volume group or logical volume - there is a chance you could lose data depending on how much you shrink the volume.
getsebool

44. It is possible to run scripts before a kickstart installation. This is done by...
defining a %pre section although it is rarely used
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
Apache uses port 80 for HTTP and port 443 for HTTPS.
Kickstart supports both basic and advanced partitioning (RAID/LVM).

45. What option is used to allow anonymous uploads to the FTP server?
semanage boolean -l
The anonymous_enable=YES option in the main config file allows anonymous uploads.
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.
The yum and rpm commands are used for package management.

46. What file needs to be edited so that the system will mount a file system at boot time?
The /etc/fstab file.
Stage 1: During this stage - the primary bootloader is read into memory by the BIOS from the MBR. Stage 1.5: During this stage - the bootloader is read into memory by the stage 1 bootloader (only if necessary). Stage 2: During this stage - the bootlo
Use the yum groupinstall command to install multiple packages in a single group at once.
useradd -c "Jr Admin" George

47. What directory is used to represent the virtual file system created by the kernel?
By default - Squid runs on port 3128.
A soft limit acts like an alarm - signaling you when you are reaching your limit. If you don't specify a grace period - the soft limit is the max. A hard limit is required only when a grace period exists. It is the max limit you can hit before your g
Use the ps command to view processes and their CPU usage.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.

48. How do you run a command with elevated privileges?
alternatives --config mta
semanage boolean -l
The lastlog and faillog commands are used to view user login-related events?
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.

49. What command can you use to create a file system?
mkfs.ext4
The mount command lists all currently mounted file systems.
Apache uses port 80 for HTTP and port 443 for HTTPS.
choose which mode you'd like it to operate in

50. Red Hat Enterprise Linux 6 is the only version that officially supports _______
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.
VNC is used to control a remote desktop session.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
LUKS encryption