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 is the difference between the update (-U) and install (-i) options when using rpm to update the kernel?
You should never use the -U option because it erases the prior kernel when updating. This leaves you with no fallback kernel should your system not boot properly.
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
The virsh command is used to manage virtual guests.
The NFS service uses TCP port 2049 by default.

2. The package selection screen allows you to install any software you want during the installation process as long as...
Enforcing during installation
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.
you have access to the correct packages or repositories.

3. What command and options can you use to update the time?
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
generates errors under Red Hat Enterprise Linux 6
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
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.

4. What does the partprobe command do?
Use the setgid flag to create the appropriate permissions (chmod 2770).
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
repquota
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.

5. What file needs to be edited so that the system will mount a file system at boot time?
halts the system
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514
SELinux Booleans provide restrictions to different aspects of a service.
The /etc/fstab file.

6. To create a RAID or LVM partition using kickstart
Kickstart supports both basic and advanced partitioning (RAID/LVM).
The three utilities are: route - ping - and nslookup.
You add your action to the end of the /home/user01/.bashrc 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.

7. 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...

8. How can you check the currently mounted file systems?
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.
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.
entering rescue mode and repairing the problem.
The mount command lists all currently mounted file systems.

9. What is a swap? Is it created as a partition or device file?
user's home directory in the /etc/skel directory
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
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 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.

10. A PXE server eases the automation process but isn't required for...
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
kickstart installations to work
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 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.

11. What client-side command can you use to test your FTP server connection?
The tcpdump command is used to monitor network connections on different interfaces.
The lftp command can be used on a client to test FTP server connections.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
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.

12. What command (and options) can be used to create a user named George with the description "Jr Admin"?
useradd -c "Jr Admin" George
getsebool
For Apache to run a secure site - the mod_ssl package is required to be installed.
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.

13. How can you change the security context of a directory to work with Apache?
This chapter described tdbsm and smbpasswd back-end authentication.
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
Using the chcon command - you can change the context of a file to work with Apache.
The lastlog and faillog commands are used to view user login-related events?

14. How would you disable SELinux protection for NFS - allowing shares to be read/write?
You must open TCP ports 20 and 21 for the FTP server to function properly.
support TCP Wrappers
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.
setsebool -P nfs_export_all_rw=1

15. Where are Yum repository config files located?
Use the setgid flag to create the appropriate permissions (chmod 2770).
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
The lftp command can be used on a client to test FTP server connections.
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.

16. The ____________ is available for each share.
browseable option
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
The rpm command can operate in install - query - or verify modes.
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.

17. What option can you change in the rsyslog config file to accept remote logs (acting as a centralized logging server)?
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.

18. What file is used to maintain custom parameters for the kernel during system boot?
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
A user's home directory is created under the /home directory.
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
Version 2 is the latest and most secure version of SSH.

19. Is it possible to share files among groups - What permissions would you set on the directory to accomplish file sharing if possible?
generates errors under Red Hat Enterprise Linux 6
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
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 setgid flag to create the appropriate permissions (chmod 2770).

20. What command can you use to test the config files before starting the DNS service?
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
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.
You can use the authconfig-tui command or the authconfig command.
service named configtest

21. What command can you use to manage system services?
The service command is used to start - stop - and manage system services.
run on any port you'd like (provided that port is available)
halts the system
browseable option

22. What are the three different types of RAID described in this chapter?
getsebool -a | grep http
The lftp command can be used on a client to test FTP server connections.
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.

23. What port does the rndc utility listen on by default?
The two main config files are master.cf and main.cf.
By default - the rndc utility listens on port 953.
semanage boolean -l
Use the ps command to view processes and their CPU usage.

24. The default SMTP service has been changed from _________ to Postfix in Red Hat Enterprise Linux 6.
Sendmail
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.
The NFS service uses TCP port 2049 by default.
via the command line

25. The firewall service is...
enabled by default
chkconfig—list
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
By default - Squid runs on port 3128.

26. What command and option do you use to view the description of Boolean values?
semanage boolean -l
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.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
You can use the authconfig-tui command or the authconfig command.

27. Which version of SSH should you use?
service httpd configtest
defining a %pre section although it is rarely used
The print option is used with both the fdisk and parted commands to display the current partition tables.
Version 2 is the latest and most secure version of SSH.

28. Are additional packages besides httpd required for a secure website - If so - what are they?
getfacl
For Apache to run a secure site - the mod_ssl package is required to be installed.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
entering rescue mode and repairing the problem.

29. Can you put your /boot partition on a RAID 5 array?
VNC is used to control a remote desktop session.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
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.
mkfs.ext4

30. What command can you use to view mounted Samba shares?
user's home directory in the /etc/skel directory
The smbstatus command shows you currently mounted Samba resources.
You must open TCP ports 20 and 21 for the FTP server to function properly.
support TCP Wrappers

31. How can you verify the status of the SSH service after the system has booted?
A user's home directory is created under the /home directory.
service sshd statuts
The /etc/fstab file.
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.

32. Which log file is used to keep track of policy violations?
getsebool
support TCP Wrappers
The /var/log/audit/audit.log file contains all policy violations.
Typing the mail or mutt command allows you to read mail from the command line.

33. If a package is built on an RHEL6 system and deployed to a custom RHEL5 repository - are RHEL5 systems able to use it?
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
kickstart installations to work
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.
run on any port you'd like (provided that port is available)

34. What is SSH used for?
The lastlog and faillog commands are used to view user login-related events?
SSH is used for secure remote management of Linux systems.
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
The yum and rpm commands are used for package management.

35. What command can you use to get information about logical volumes?
lvdisplay
getsebool
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
Physical volumes - volume groups - and logical volumes.

36. What is the xinetd service used for?
The /etc/fstab file.
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.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.

37. What happens to jobs that are scheduled to run while the system is off?
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.
cat /proc/mdstat
Apache uses port 80 for HTTP and port 443 for HTTPS.
createrepo

38. What is the /var/lib/nfs/etab file used for?
The SMTP service runs on TCP port 110.
via the command line
The /var/lib/nfs/etab file is used to keep track of currently exported resources.
cat /proc/mdstat

39. What is the name of the package that allows you to install VNC?
getsebool
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
support TCP Wrappers

40. What are the two types of back-end authentication mechanisms discussed in this chapter?
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.
Apache uses port 80 for HTTP and port 443 for HTTPS.
This chapter described tdbsm and smbpasswd back-end authentication.

41. What is the difference between an A record and a PTR record?
DNS uses port 53.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
serve both files and printers to users
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.

42. How would you install a group of packages all at a single time?
rpcbind service
The print option is used with both the fdisk and parted commands to display the current partition tables.
Use the yum groupinstall command to install multiple packages in a single group at once.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.

43. What directory is used to represent the virtual file system created by the kernel?
Enforcing during installation
repquota
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.

44. What are the three modes in which the rpm command can operate?
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.
Typing the mail or mutt command allows you to read mail from the command line.
The rpm command can operate in install - query - or verify modes.
service dhcpd configtest

45. How can virtual hosts be used?
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
You add your action to the end of the /home/user01/.bashrc file.
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.
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.

46. What commands can you use to add a client machine to an LDAP server?
setsebool -P nfs_export_all_rw=1
You can use the authconfig-tui command or the authconfig command.
The tcpdump command is used to monitor network connections on different interfaces.
The /var/log/audit/audit.log file contains all policy violations.

47. SSH does...
Use the route command with the add option to create a static route.
support TCP Wrappers
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.

48. What are the five required directories when building RPMS?
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.
chcon
SELinux provides enhanced granular security for the Linux operating system.

49. What command do you use to report information on quota usage?
The file system where quotas will be implemented must be mounted with the usrquota and grpquota options before quotas will work properly.
repquota
atq
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.

50. In Red Hat Enterprise Linux 6 - the default for SELinux is _______________ (which can be changed after the installation completes). For Red Hat Enterprise Linux 5 - you were able to choose what mode you wanted SELinux to start in.
Enforcing during installation
Use the setgid flag to create the appropriate permissions (chmod 2770).
generates errors under Red Hat Enterprise Linux 6
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.