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 command do you use to report information on quota usage?
repquota
Enforcing during installation
The yum and rpm commands are used for package management.
chkconfig—list

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

3. What is NAT - How is it used?
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
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.
ifconfig
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).

4. What is the rndc utility used 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
The rndc utility provides a method for managing the DNS server remotely and securely.
service httpd configtest
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.

5. What three protocols can you use to perform network installations?
Network installations can be performed using the HTTP - FTP - and NFS protocols.
user's home directory in the /etc/skel directory
SSH is used for secure remote management of Linux systems.
This command reboots virtual guest Client04.

6. What is the last rule in the iptables file?

7. What command can you use to validate the syntax of the Apache config file?
mkfs.ext4
service httpd configtest
Apache uses port 80 for HTTP and port 443 for HTTPS.
you have access to the correct packages or repositories.

8. What does virsh reboot Client04 do?
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.
This command reboots virtual guest Client04.
Use the route command with the add option to create a static route.
support for TCP Wrappers

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

10. What options with the yum command would you use to remove a package?
Use the route command with the add option to create a static route.
The rndc utility provides a method for managing the DNS server remotely and securely.
You can use the remove or erase options with yum to remove a package.
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.

11. What critical step must you take after updating the kernel to a newer version?
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.
alternatives --config mta
defining a %pre section although it is rarely used
cat /proc/mdstat

12. Which file shows you all the client IP addresses?
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
amount of RAM
chkconfig sshd off

13. How would you view all Boolean options for the HTTP service?
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.
getsebool -a | grep http
generates errors under Red Hat Enterprise Linux 6
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. What does it mean if you ping a host and you receive the response Destination Unreachable?
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
browseable option
setsebool -P nfs_export_all_rw=1
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.

15. What command can you use to get information about logical volumes?
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
The NFS service uses TCP port 2049 by default.
lvdisplay
You must open TCP ports 20 and 21 for the FTP server to function properly.

16. What is the difference between an A record and a PTR record?
You must open TCP ports 20 and 21 for the FTP server to function properly.
Network installations can be performed using the HTTP - FTP - and NFS protocols.
The lastlog and faillog commands are used to view user login-related events?
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.

17. How can you check the currently mounted file systems?
The mount command lists all currently mounted file systems.
chkconfig—list
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
semanage boolean -l

18. GRUB has three stages. Can you name them?
getsebool -a | grep http
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
Typing the mail or mutt command allows you to read mail from the command line.
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.

19. The default SMTP service has been changed from _________ to Postfix in Red Hat Enterprise Linux 6.
Sendmail
The lftp command can be used on a client to test FTP server connections.
useradd -c "Jr Admin" George
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.

20. The ____________ is available for each share.
browseable option
You can use the remove or erase options with yum to remove a package.
ifconfig
lvdisplay

21. What happens if you call the command from question 3 with the -c option after it has already been run?
The rpm command can operate in install - query - or verify modes.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
Use the ps command to view processes and their CPU usage.
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.

22. What are the side effects of shrinking a volume group or logical volume?
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.
export one or all resources
VNC is used to control a remote desktop session.
The user_list file can be used to limit which users have access to the FTP server.

23. Is it possible to share files among groups - What permissions would you set on the directory to accomplish file sharing if possible?
Use the setgid flag to create the appropriate permissions (chmod 2770).
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 /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.
Using the chcon command - you can change the context of a file to work with Apache.

24. What port on the firewall needs to be open for the TFTP server to work?
The TFTP server uses UDP port 69.
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.
rpcbind service
The NFS service uses TCP port 2049 by default.

25. What port does the Apache web server run on - What about HTTPS?
Apache uses port 80 for HTTP and port 443 for HTTPS.
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.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.

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

27. What command can be used to view the queue for at service jobs?
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
The tcpdump command is used to monitor network connections on different interfaces.
Enforcing during installation
atq

28. What is SSH used for?
SSH is used for secure remote management of Linux systems.
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
The htpasswd command can be used to password-protect a web page.
This command reboots virtual guest Client04.

29. What command can you use to check the config file of the DHCP server?
The service command is used to start - stop - and manage system services.
DNS uses port 53.
service dhcpd configtest
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.

30. What is the superblock used for?
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
alternatives --config mta
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
You can use the remove or erase options with yum to remove a package.

31. What command (and options) can be used to create a user named George with the description "Jr Admin"?
SSH is used for secure remote management of Linux systems.
useradd -c "Jr Admin" George
By defining a %post section - you can run scripts after a kickstart installation is complete.
rpmbuild

32. To grow a file system
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.
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.
Use the resize2fs command to grow a file system.

33. What is a gateway used for on a network?
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.
Use the route command with the add option to create a static route.
Enforcing during installation
defining a %pre section although it is rarely used

34. The ______________ for Red Hat Enterprise Linux 5 or 6 includes the use of LVM.
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.
Enforcing during installation
browseable option

35. What is the benefit to using centralized authentication?

36. Red Hat Enterprise Linux 6 is the only version that officially supports _______
choose which mode you'd like it to operate in
support TCP Wrappers
LUKS encryption
By default - the rndc utility listens on port 953.

37. What option can you change in the rsyslog config file to accept remote logs (acting as a centralized logging server)?
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
The smbstatus command shows you currently mounted Samba resources.
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.

38. What option is used with both the fdisk and parted commands to display the current partition tables?
The print option is used with both the fdisk and parted commands to display the current partition tables.
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.
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.
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.

39. What client-side command can you use to test your FTP server connection?
The lftp command can be used on a client to test FTP server connections.
load balancing and redundancy benefits
The NFS service uses TCP port 2049 by default.
The user_list file can be used to limit which users have access to the FTP server.

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

41. What are the three items that make up LVM?
The -t nfs option is used with the mount command to mount NFS resources.
The /etc/fstab file.
Physical volumes - volume groups - and logical volumes.
The /var/log/audit/audit.log file contains all policy violations.

42. How would you install a group of packages all at a single time?
Use the yum groupinstall command to install multiple packages in a single group at once.
Use the setgid flag to create the appropriate permissions (chmod 2770).
support TCP Wrappers
alternatives --config mta

43. 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.
support TCP Wrappers
export one or all resources
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.

44. A slave DNS server provides...
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
By default - Squid runs on port 3128.
load balancing and redundancy benefits
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.

45. Which version of SSH should you use?
getsebool
SELinux provides enhanced granular security for the Linux operating system.
Version 2 is the latest and most secure version of SSH.
The SMTP service runs on TCP port 110.

46. What does the rdnc-confgen command do?
used for kickstart and/or network installs
The SMTP service runs on TCP port 110.
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.

47. What option is used to allow anonymous uploads to the FTP server?
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 rpm command can operate in install - query - or verify modes.
cat /proc/mdstat
The anonymous_enable=YES option in the main config file allows anonymous uploads.

48. What command can you use to create a file system?
support for TCP Wrappers
amount of RAM
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
mkfs.ext4

49. The firewall service is...
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.
enabled by default
The two main config files are master.cf and main.cf.
chkconfig xinetd --list

50. What does S12rsyslog in the /etc/rc.d/rc2.d directory mean?
Enforcing during installation
user's home directory in the /etc/skel directory
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.
run on any port you'd like (provided that port is available)