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. The ______________ for Red Hat Enterprise Linux 5 or 6 includes the use of LVM.
The NFS service uses TCP port 2049 by default.
The nfsstat command can be used to view NFS statistics.
via the command line
Enforcing during installation

2. Are additional packages besides httpd required for a secure website - If so - what are they?
SSH is used for secure remote management of Linux systems.
DNS uses port 53.
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.
For Apache to run a secure site - the mod_ssl package is required to be installed.

3. 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.
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.
semanage boolean -l
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

4. To create a RAID or LVM partition using kickstart
Kickstart supports both basic and advanced partitioning (RAID/LVM).
DNS uses port 53.
Enforcing during installation
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.

5. What is the default port that Squid runs on?
By default - Squid runs on port 3128.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
The SMTP service runs on TCP port 110.
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.

6. What command can you use to create a password-protected page?
The htpasswd command can be used to password-protect a web page.
Network installations can be performed using the HTTP - FTP - and NFS protocols.
The /var/log/audit/audit.log file contains all policy violations.
enabled by default

7. Do you need to write changes to the disk when using the parted command? What about fdisk?
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
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.
createrepo
The virsh command is used to manage virtual guests.

8. What command can you use to manage system services?
service named configtest
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 service command is used to start - stop - and manage system services.
service httpd configtest

9. Can you name the two commands that can be used to view the free space on the system?
SELinux provides enhanced granular security for the Linux operating system.
The two main config files are master.cf and main.cf.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
The du and df commands are used to view available space on the system.

10. What port must be opened on the firewall for DNS?
service named configtest
A virtual host is a way of hosting multiple sites using a single IP address.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
DNS uses port 53.

11. What is the top command used for?
Use the top command to view CPU and memory usage.
cat /proc/mdstat
export one or all resources
defining a %pre section although it is rarely used

12. What three commands can you use to help verify that the DNS server is functioning properly?
choose which mode you'd like it to operate in
The dig - host - and ping commands can be used to test DNS server functionality.
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.
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.

13. Runlevel 0 ___________. Runlevel 6 reboots the system.
The /var/lib/nfs/etab file is used to keep track of currently exported resources.
getsebool -a | grep http
halts the system
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.

14. How do you run a command with elevated privileges?
The /var/log/audit/audit.log file contains all policy violations.
Use the ps command to view processes and their CPU usage.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
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.

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

16. What is the format of the /etc/shadow file?
Sendmail
Use the ps command to view processes and their CPU usage.
chkconfig sshd off
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.

17. It is possible to run scripts before a kickstart installation. This is done by...
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.
defining a %pre section although it is rarely used
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.
The two main config files are master.cf and main.cf.

18. Which file contains all messages generated during installation that can be used for troubleshooting if the need arises?
DNS uses port 53.
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.
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.
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.

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

20. How can virtual hosts be used?
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.
You add your action to the end of the /home/user01/.bashrc file.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
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.

21. What option is used with both the fdisk and parted commands to display the current partition tables?
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
The print option is used with both the fdisk and parted commands to display the current partition tables.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.

22. What happens if you call the command from question 3 with the -c option after it has already been run?
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
useradd -c "Jr Admin" George
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
halts the system

23. What does the rdnc-confgen command do?
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
This chapter described tdbsm and smbpasswd back-end authentication.
support TCP Wrappers
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.

24. What is a gateway used for on a network?
The tcpdump command is used to monitor network connections on different interfaces.
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.
generates errors under Red Hat Enterprise Linux 6
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.

25. How would you go about creating a static route?
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.
support for TCP Wrappers
Use the route command with the add option to create a static route.
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.

26. How would you disable SELinux protection for NFS - allowing shares to be read/write?
Use the top command to view CPU and memory usage.
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
setsebool -P nfs_export_all_rw=1
You add your action to the end of the /home/user01/.bashrc file.

27. 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...

28. Can you put your /boot partition on a RAID 5 array?
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.
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
entering rescue mode and repairing the problem.
Use the yum groupinstall command to install multiple packages in a single group at once.

29. What option is used to allow anonymous uploads to the FTP server?
choose which mode you'd like it to operate in
Use the route command with the add option to create a static route.
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
The anonymous_enable=YES option in the main config file allows anonymous uploads.

30. What command can you use to test connectivity to another host?
The dig - host - and ping commands can be used to test DNS server functionality.
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 ping command can be used to verify connectivity to another host.
A user's home directory is created under the /home directory.

31. A service needs to have _______________ to be able to use it.
The three utilities are: route - ping - and nslookup.
support for TCP Wrappers
via the command line
The service command is used to start - stop - and manage system services.

32. How can you change the security context of a directory to work with Apache?
Using the chcon command - you can change the context of a file to work with Apache.
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.
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.

33. What commands can you use to add a client machine to an LDAP server?
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
LUKS encryption
repquota
You can use the authconfig-tui command or the authconfig command.

34. What does the following firewall rule accomplish: iptables -I INPUT 5 -p tcp -m tcp --dport 80 -j ACCEPT?
By default - Squid runs on port 3128.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
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.
entering rescue mode and repairing the problem.

35. How can you check the currently mounted file systems?
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
generates errors under Red Hat Enterprise Linux 6
For Apache to run a secure site - the mod_ssl package is required to be installed.
The mount command lists all currently mounted file systems.

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

37. Can you name three utilities that can be used for network or DNS client troubleshooting?
mkfs.ext4
you have access to the correct packages or repositories.
The vsftpd package is used to install an FTP server.
The three utilities are: route - ping - and nslookup.

38. You must dictate the ____________ you want allocated to your virtual machine when you create it.
The TFTP server uses UDP port 69.
The du and df commands are used to view available space on the system.
amount of RAM
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.

39. What command can you use to create a new SSL certificate?
repquota
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.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
load balancing and redundancy benefits

40. To grow a file system
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
This chapter described tdbsm and smbpasswd back-end authentication.
Use the resize2fs command to grow a file system.
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.

41. What file needs to be edited so that the system will mount a file system at boot time?
The /etc/fstab file.
chkconfig—list
The du and df commands are used to view available space on the system.
By default - Squid runs on port 3128.

42. What command can you use to change the context of files?
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
lvdisplay
The vsftpd package is used to install an FTP server.
chcon

43. What command would you use to create a group - to add the user George to the group?
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
Version 2 is the latest and most secure version of SSH.
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
Apache uses port 80 for HTTP and port 443 for HTTPS.

44. What three components are needed to fully automate a kickstart installation?
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
chcon
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.

45. What is a swap? Is it created as a partition or device file?
getfacl
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.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
Use the top command to view CPU and memory usage.

46. What command disables the SSH service from running when the system boots?
chkconfig sshd off
The TFTP server uses UDP port 69.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
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.

47. A slave DNS server provides...
The ping command can be used to verify connectivity to another host.
Use the setgid flag to create the appropriate permissions (chmod 2770).
load balancing and redundancy benefits
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George

48. What does the testparm command do?
DNS uses port 53.
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.
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
Kickstart supports both basic and advanced partitioning (RAID/LVM).

49. Which file shows you all the client IP addresses?
repquota
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
chkconfig—list
service named configtest

50. What command can you use to create a file system?
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.
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.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
mkfs.ext4