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. There are four types of DNS servers. Name them.
The four types of DNS servers are master - slave - caching-only - and forwarding.
export one or all resources
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.
Physical volumes - volume groups - and logical volumes.

2. Before you work with ACLs - what do you need to do to the file system?
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
By defining a %post section - you can run scripts after a kickstart installation is complete.
Use the top command to view CPU and memory usage.
Use the route command with the add option to create a static route.

3. What command and option can you use to enable a service to start on boot?
Yum repository config files (.repo files) are located in the /etc/yum.repos.d directory. You can also make direct entries into the main /etc/yum.conf file.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
amount of RAM
The mount command lists all currently mounted file systems.

4. Can you name the two commands that can be used to view the free space on the system?
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
The du and df commands are used to view available space on the system.
Kickstart supports both basic and advanced partitioning (RAID/LVM).

5. What port must be opened on the firewall for DNS?
setsebool -P nfs_export_all_rw=1
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
DNS uses port 53.
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.

6. What command (and options) can be used to create a user named George with the description "Jr Admin"?
Yum repository config files (.repo files) are located in the /etc/yum.repos.d directory. You can also make direct entries into the main /etc/yum.conf file.
The /var/log/audit/audit.log file contains all policy violations.
DNS uses port 53.
useradd -c "Jr Admin" George

7. What is VNC?
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.
service httpd configtest
VNC is used to control a remote desktop session.

8. What client-side command can you use to test your FTP server connection?
alternatives --config mta
defining a %pre section although it is rarely used
The lftp command can be used on a client to test FTP server connections.
SELinux Booleans provide restrictions to different aspects of a service.

9. Are additional packages besides httpd required for a secure website - If so - what are they?
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
For Apache to run a secure site - the mod_ssl package is required to be installed.
kickstart installations to work
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.

10. A PXE server eases the automation process but isn't required for...
rpcbind service
The lftp command can be used on a client to test FTP server connections.
kickstart installations to work
A user's home directory is created under the /home directory.

11. What command-line program can you use to check your mail?
The TFTP server uses UDP port 69.
The /var/log/audit/audit.log file contains all policy violations.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
Typing the mail or mutt command allows you to read mail from the command line.

12. The ______________ for Red Hat Enterprise Linux 5 or 6 includes the use of LVM.
Enforcing during installation
alternatives --config mta
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.
Typing the mail or mutt command allows you to read mail from the command line.

13. What does the following firewall rule accomplish: iptables -I INPUT 5 -p tcp -m tcp --dport 80 -j ACCEPT?
load balancing and redundancy benefits
getfacl
amount of RAM
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.

14. How can you display all virtual guests after they're connected to a hypervisor?
getfacl
The du and df commands are used to view available space on the system.
cat /proc/mdstat
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.

15. What two ports should be opened on the firewall for the FTP server to function properly?
service dhcpd configtest
You must open TCP ports 20 and 21 for the FTP server to function properly.
lvdisplay
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.

16. Through its main config file - SSH can be configured to...

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

18. How would you go about creating a static route?
The NFS service uses TCP port 2049 by default.
Use the route command with the add option to create a static route.
Use the resize2fs command to grow a file system.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.

19. What command can you use to create your own repositories?
createrepo
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 vsftpd package is used to install an FTP server.

20. How can you list all services on the system to tell whether they will boot during startup?
chkconfig—list
getsebool
SELinux Booleans provide restrictions to different aspects of a service.
The virsh command is used to manage virtual guests.

21. What is SSH used for?
The vsftpd package is used to install an 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.
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.
SSH is used for secure remote management of Linux systems.

22. The at command is used to ____________. The cron service handles reoccurring system jobs.
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.
The tcpdump command is used to monitor network connections on different interfaces.
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
schedule one-time-only jobs

23. For Red Hat Enterprise Linux 6 - SELinux comes set up in enforcing mode. When installing Red Hat Enterprise Linux 5 - you have the option to...

24. You must dictate the ____________ you want allocated to your virtual machine when you create it.
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
amount of RAM
Kickstart supports both basic and advanced partitioning (RAID/LVM).
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.

25. What are SELinux Booleans?
SELinux Booleans provide restrictions to different aspects of a service.
load balancing and redundancy benefits
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.

26. Samba servers can...
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.
serve both files and printers to users
This command reboots virtual guest Client04.
The TFTP server uses UDP port 69.

27. What options with the yum command would you use to remove a package?
You can use the remove or erase options with yum to remove a package.
lvdisplay
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.

28. How can you check the currently mounted file systems?
The two main config files are master.cf and main.cf.
The user_list file can be used to limit which users have access to the FTP server.
The htpasswd command can be used to password-protect a web page.
The mount command lists all currently mounted file systems.

29. The package selection screen allows you to install any software you want during the installation process as long as...
you have access to the correct packages or repositories.
createrepo
You can use the authconfig-tui command or the authconfig command.
export one or all resources

30. GRUB has three stages. Can you name them?
you have access to the correct packages or repositories.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
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

31. 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.
support for TCP Wrappers
The lastlog and faillog commands are used to view user login-related events?
The two main config files are master.cf and main.cf.

32. Which file shows you all the client IP addresses?
The anonymous_enable=YES option in the main config file allows anonymous uploads.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
DNS uses port 53.
getsebool -a | grep http

33. The exportfs command is used to...
For Apache to run a secure site - the mod_ssl package is required to be installed.
export one or all resources
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.

34. What option at the GRUB boot menu can you use to append something to a kernel?
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
The mount command lists all currently mounted file systems.
export one or all resources

35. By default - what is the path to a user's home directory?

36. What command and option do you use to view the description of Boolean values?
halts the system
semanage boolean -l
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
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.

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

38. What are the two types of back-end authentication mechanisms discussed in this chapter?
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.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
This chapter described tdbsm and smbpasswd back-end authentication.
useradd -c "Jr Admin" George

39. What command can you use to create a password-protected page?
schedule one-time-only jobs
Network installations can be performed using the HTTP - FTP - and NFS protocols.
The htpasswd command can be used to password-protect a web page.
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.

40. Editing the /etc/xinetd.d/tftp file and enabling the service are the same as running the chkconfig tftp on command. Both of these actions...
A virtual host is a way of hosting multiple sites using a single IP address.
have the same effect
Kickstart supports both basic and advanced partitioning (RAID/LVM).
setsebool -P nfs_export_all_rw=1

41. What does S12rsyslog in the /etc/rc.d/rc2.d directory mean?
service httpd configtest
The print option is used with both the fdisk and parted commands to display the current partition tables.
A virtual host is a way of hosting multiple sites using a single IP address.
When the system enters into runlevel 2 - the rsyslog service has a priority of 12 when starting. Anything with a lower number (or the same number and lower first letter) starts before the rsyslog service.

42. What command do you use to change the permissions on a file or directory - To change ownership?
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.
This chapter described tdbsm and smbpasswd back-end authentication.
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.
load balancing and redundancy benefits

43. What commands can you use to add a client machine to an LDAP server?
You can use the authconfig-tui command or the authconfig command.
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.
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.

44. What command can you use to create a new SSL certificate?
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
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.

45. What command can you use to view system processes and their CPU usage?
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.
Use the ps command to view processes and their CPU usage.
The two main config files are master.cf and main.cf.
The DHCP server listens on port 67 by default.

46. What is the biggest benefit to using LVM over basic partitions?
The yum and rpm commands are used for package management.
The vsftpd package is used to install an FTP server.
You have the flexibility to resize and add new volumes on the fly. With basic partitions - any time that you want to make a change - you need to destroy the partition and create it again.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.

47. Explain the difference between soft and hard limits in quotas.

48. What command can you use to check the config file of the DHCP server?
service dhcpd configtest
The file system where quotas will be implemented must be mounted with the usrquota and grpquota options before quotas will work properly.
kickstart installations to work
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George

49. What port does NFS use by default?
The anonymous_enable=YES option in the main config file allows anonymous uploads.
cat /proc/mdstat
The NFS service uses TCP port 2049 by default.
serve both files and printers to users

50. Is it possible to share files among groups - What permissions would you set on the directory to accomplish file sharing if possible?
You add your action to the end of the /home/user01/.bashrc file.
The rndc utility provides a method for managing the DNS server remotely and securely.
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.
Use the setgid flag to create the appropriate permissions (chmod 2770).