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. Can you name three utilities that can be used for network or DNS client troubleshooting?
chkconfig xinetd --list
rpcbind service
The three utilities are: route - ping - and nslookup.
Version 2 is the latest and most secure version of SSH.

2. What command displays your current interfaces and IP address?
You must open TCP ports 20 and 21 for the FTP server to function properly.
Apache uses port 80 for HTTP and port 443 for HTTPS.
ifconfig
By default - the rndc utility listens on port 953.

3. The ____________ is available for each share.
You should never allow remote root access. Should your root account become compromised and you use the same password - someone could gain access to all your systems. You also don't want the most powerful user of your system (with no accountability) l
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.
browseable option
Physical volumes - volume groups - and logical volumes.

4. Should you allow remote root access - Why or why not?

5. What command can you use to create a new SSL certificate?
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
The NFS service uses TCP port 2049 by default.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
The vsftpd package is used to install an FTP server.

6. What is a swap? Is it created as a partition or device file?
service dhcpd configtest
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.
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.
A user's home directory is created under the /home directory.

7. Are additional packages besides httpd required for a secure website - If so - what are they?
getsebool -a | grep http
atq
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
For Apache to run a secure site - the mod_ssl package is required to be installed.

8. What are the two config files for Postfix called?
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
The three utilities are: route - ping - and nslookup.
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 two main config files are master.cf and main.cf.

9. What command and option do you use to view the description of Boolean values?
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
semanage boolean -l
The htpasswd command can be used to password-protect a web page.

10. What two commands are special for dealing with user login events?
The lastlog and faillog commands are used to view user login-related events?
load balancing and redundancy benefits
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.
Network address translation (NAT) maintains a table that allows the use of multiple internal IP addresses to a multiple public IP address (called address translation). It can also be used for one-to-one or one-to-many relationships as well.

11. What client-side command can you use to test your FTP server connection?
serve both files and printers to users
Version 2 is the latest and most secure version of SSH.
The lftp command can be used on a client to test FTP server connections.
useradd -c "Jr Admin" George

12. How do you run a command with elevated privileges?
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
A large warning message appears indicating that the key doesn't match the host you are connecting to. You have to remove the key/host pair from the known_hosts file to proceed.
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.

13. What is the difference between an A record and a PTR record?
used for kickstart and/or network installs
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.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.

14. What three commands can you use to help verify that the DNS server is functioning properly?
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.
semanage boolean -l
The lastlog and faillog commands are used to view user login-related events?
The dig - host - and ping commands can be used to test DNS server functionality.

15. What three protocols can you use to perform network installations?
have the same effect
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.
Network installations can be performed using the HTTP - FTP - and NFS protocols.
repquota

16. What happens if you call the command from question 3 with the -c option after it has already been run?
The dig - host - and ping commands can be used to test DNS server functionality.
have the same effect
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
A large warning message appears indicating that the key doesn't match the host you are connecting to. You have to remove the key/host pair from the known_hosts file to proceed.

17. What command can you use to manage system services?
The user_list file can be used to limit which users have access to the FTP server.
setsebool -P nfs_export_all_rw=1
The service command is used to start - stop - and manage system services.
Network installations can be performed using the HTTP - FTP - and NFS protocols.

18. What is the xinetd service used for?
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.
You must open TCP ports 20 and 21 for the FTP server to function properly.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
The du and df commands are used to view available space on the system.

19. What directory is used to represent the virtual file system created by the kernel?
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.
load balancing and redundancy benefits
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.

20. How would you disable SELinux protection for NFS - allowing shares to be read/write?
By default - the rndc utility listens on port 953.
getsebool -a | grep http
setsebool -P nfs_export_all_rw=1
defining a %pre section although it is rarely used

21. A service needs to have _______________ to be able to use it.
support for TCP Wrappers
load balancing and redundancy benefits
The user_list file can be used to limit which users have access to the FTP server.
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.

22. How can you check the currently mounted file systems?
Typing the mail or mutt command allows you to read mail from the command line.
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
The mount command lists all currently mounted file systems.
setsebool -P nfs_export_all_rw=1

23. What happens if a host changes its IP address and the keys don't match?

24. The default SMTP service has been changed from _________ to Postfix in Red Hat Enterprise Linux 6.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
The du and df commands are used to view available space on the system.
Sendmail
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 is the point of using SELinux?
SELinux provides enhanced granular security for the Linux operating system.
service dhcpd configtest
schedule one-time-only jobs
you have access to the correct packages or repositories.

26. Which file contains all messages generated during installation that can be used for troubleshooting if the need arises?
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.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
user's home directory in the /etc/skel directory
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.

27. 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...
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
have the same effect
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.

28. The INPUT chain being used is the default under Red Hat Enterprise Linux 5. This rule...
Using the chcon command - you can change the context of a file to work with Apache.
lvdisplay
choose which mode you'd like it to operate in
generates errors under Red Hat Enterprise Linux 6

29. Where are Yum repository config files located?
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.
DNS uses port 53.
Using the chcon command - you can change the context of a file to work with Apache.
The lftp command can be used on a client to test FTP server connections.

30. What is NAT - How is it used?
ifconfig
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
The du and df commands are used to view available space on the system.
Network address translation (NAT) maintains a table that allows the use of multiple internal IP addresses to a multiple public IP address (called address translation). It can also be used for one-to-one or one-to-many relationships as well.

31. How can virtual hosts be used?
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
The three utilities are: route - ping - and nslookup.
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.

32. What command can you use to create your own repositories?
createrepo
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.
support TCP Wrappers
ifconfig

33. How can you change the security context of a directory to work with Apache?
chkconfig xinetd --list
Version 2 is the latest and most secure version of SSH.
browseable option
Using the chcon command - you can change the context of a file to work with Apache.

34. What command can be used to view the queue for at service jobs?
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
support TCP Wrappers
atq
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.

35. What command can you use to view the current ACL on a file?
getfacl
The yum and rpm commands are used for package management.
This chapter described tdbsm and smbpasswd back-end authentication.
chcon

36. What options with the yum command would you use to remove a package?
repquota
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
By defining a %post section - you can run scripts after a kickstart installation is complete.
You can use the remove or erase options with yum to remove a package.

37. What option at the GRUB boot menu can you use to append something to a kernel?
The SSH service is almost always installed by default in Red Hat. It uses TCP port 22 - and this port is open on the default firewall rules.
service dhcpd configtest
You add your action to the end of the /home/user01/.bashrc file.
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.

38. What port does the DHCP server listen on by default?
The DHCP server listens on port 67 by default.
Kickstart supports both basic and advanced partitioning (RAID/LVM).
enabled by default
The /var/log/audit/audit.log file contains all policy violations.

39. FTP is one of three protocols ______________. The other two protocols are NFS and HTTP.
used for kickstart and/or network installs
The rpm command can operate in install - query - or verify modes.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
The vsftpd package is used to install an FTP server.

40. What is the difference between an ext2 and ext3 file system?

41. It is possible to run scripts before a kickstart installation. This is done by...
The virsh command is used to manage virtual guests.
service dhcpd configtest
cat /proc/mdstat
defining a %pre section although it is rarely used

42. What is PAM used for?
PAM is used as a modular way to leverage security. In this chapter - the main function we discussed was for managing password policies and complexity.
Use the route command with the add option to create a static route.
A user's home directory is created under the /home directory.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.

43. What command is used to create a user for Samba?
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
The virsh command is used to manage virtual guests.
The smbpasswd command is used to create Samba users.

44. The firewall service is...
enabled by default
The smbpasswd command is used to create Samba users.
rpmbuild
repquota

45. What is the benefit to using centralized authentication?

46. What is the format of the /etc/shadow file?
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
Use the top command to view CPU and memory usage.
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.
By default - the rndc utility listens on port 953.

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

48. What are SELinux Booleans?
support TCP Wrappers
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.
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
SELinux Booleans provide restrictions to different aspects of a service.

49. How can you list all services on the system to tell whether they will boot during startup?
The yum and rpm commands are used for package management.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
rpcbind service
chkconfig—list

50. What is the rndc utility used for?
choose which mode you'd like it to operate in
The rndc utility provides a method for managing the DNS server remotely and securely.
The yum and rpm commands are used for package management.
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.