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 port does the DHCP server listen on by default?
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 DHCP server listens on port 67 by default.
For Apache to run a secure site - the mod_ssl package is required to be installed.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.

2. To export directories as resources - what file needs to be edited?

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

4. The old SysInit scripts have been replaced in Red Hat Enterprise Linux 6 for what new boot utility?
Version 2 is the latest and most secure version of SSH.
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 htpasswd command can be used to password-protect a web page.

5. What command disables the SSH service from running when the system boots?
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
LUKS encryption
chkconfig sshd off
The nfsstat command can be used to view NFS statistics.

6. 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.
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
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.
A virtual host is a way of hosting multiple sites using a single IP address.

7. What command can you use to create a password-protected page?
chkconfig—list
generates errors under Red Hat Enterprise Linux 6
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
The htpasswd command can be used to password-protect a web page.

8. What is the benefit to using centralized authentication?

9. If you want a specific action to take place when user01 logs in to the system - which file would you edit?
The last rule is always an implicit deny statement rejecting anything that wasn't matched by previous rules.
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.
You add your action to the end of the /home/user01/.bashrc file.
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.

10. 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.
getfacl
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.

11. What two commands are special for dealing with user login events?
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.
The lastlog and faillog commands are used to view user login-related events?
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.

12. What command can you use to test connectivity to another host?
support TCP Wrappers
The ping command can be used to verify connectivity to another host.
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 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.

13. The ____________ is available for each share.
Use the setgid flag to create the appropriate permissions (chmod 2770).
browseable option
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.
The /var/log/audit/audit.log file contains all policy violations.

14. What does the testparm command do?
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.
Network installations can be performed using the HTTP - FTP - and NFS protocols.
schedule one-time-only jobs

15. How can you check the currently mounted file systems?
The mount command lists all currently mounted file systems.
SELinux Booleans provide restrictions to different aspects of a service.
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.

16. What is SSH used for?
A virtual host is a way of hosting multiple sites using a single IP address.
SSH is used for secure remote management of Linux systems.
support TCP Wrappers
By default - the rndc utility listens on port 953.

17. The INPUT chain being used is the default under Red Hat Enterprise Linux 5. This rule...
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
enabled by default
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.

18. 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.
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
chkconfig—list
Enforcing during installation
mkfs.ext4

19. Samba servers can...
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
LUKS encryption
serve both files and printers to users

20. What are the five required directories when building RPMS?
service httpd configtest
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.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.

21. What file is used to maintain custom parameters for the kernel during system boot?
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
lvdisplay
export one or all resources

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

23. What three protocols can you use to perform network installations?
Network installations can be performed using the HTTP - FTP - and NFS protocols.
useradd -c "Jr Admin" George
kickstart installations to work
lvdisplay

24. What command is used to create a user for Samba?
The smbpasswd command is used to create Samba users.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
The three utilities are: route - ping - and nslookup.
load balancing and redundancy benefits

25. What does the partprobe command do?
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
The dig - host - and ping commands can be used to test DNS server functionality.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
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.

26. What command can be used to easily list all the options in the FTP main config file?
Enforcing during installation
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
The tcpdump command is used to monitor network connections on different interfaces.
you have access to the correct packages or repositories.

27. What does the following firewall rule accomplish: iptables -I INPUT 5 -p tcp -m tcp --dport 80 -j ACCEPT?
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.
enabled by default
The virsh command is used to manage virtual guests.
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.

28. 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...
By default - the rndc utility listens on port 953.
have the same effect
Typing the mail or mutt command allows you to read mail from the command line.
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.

29. What is the difference between an A record and a PTR record?
enabled by default
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
The lastlog and faillog commands are used to view user login-related events?
chkconfig xinetd --list

30. What option needs to be used with the mount command to mount an NFS resource?
VNC is used to control a remote desktop session.
generates errors under Red Hat Enterprise Linux 6
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
The -t nfs option is used with the mount command to mount NFS resources.

31. Can you name the two commands that can be used to view the free space on the system?
You must open TCP ports 20 and 21 for the FTP server to function properly.
The du and df commands are used to view available space on the system.
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.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.

32. What option would you use to query an installed package using the rpm command?
By default - Squid runs on port 3128.
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.
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
service httpd configtest

33. What does it mean if you ping a host and you receive the response Destination Unreachable?
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.
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
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.

34. What command can be used to view the queue for at service jobs?
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
atq
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.
getsebool -a | grep http

35. What option is used to allow anonymous uploads to the FTP server?
Use the top command to view CPU and memory usage.
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.
The anonymous_enable=YES option in the main config file allows anonymous uploads.
Use the yum groupinstall command to install multiple packages in a single group at once.

36. What benefit does a web proxy provide to your network?
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
setsebool -P nfs_export_all_rw=1

37. What directory is used to represent the virtual file system created by the kernel?
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.
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.
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.

38. Where are Yum repository config files located?
support for TCP Wrappers
support TCP Wrappers
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
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.

39. The package selection screen allows you to install any software you want during the installation process as long as...
service named configtest
you have access to the correct packages or repositories.
The service command is used to start - stop - and manage system services.
The NFS service uses TCP port 2049 by default.

40. What command can you use to create your own repositories?
createrepo
used for kickstart and/or network installs
Kickstart supports both basic and advanced partitioning (RAID/LVM).
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.

41. What is the superblock used for?
Kickstart supports both basic and advanced partitioning (RAID/LVM).
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
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.
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.

42. How would you disable SELinux protection for NFS - allowing shares to be read/write?
The ping command can be used to verify connectivity to another host.
setsebool -P nfs_export_all_rw=1
The print option is used with both the fdisk and parted commands to display the current partition tables.
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.

43. The portmap service was replaced by the ______________ in Red Hat Enterprise Linux 6.
The vsftpd package is used to install an FTP server.
rpcbind service
The rndc utility provides a method for managing the DNS server remotely and securely.
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.

44. How would you go about creating a static route?
used for kickstart and/or network installs
LUKS encryption
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
Use the route command with the add option to create a static route.

45. A slave DNS server provides...
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.
load balancing and redundancy benefits
Enforcing during installation
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.

46. What client-side command can you use to test your FTP server connection?
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.
A virtual host is a way of hosting multiple sites using a single IP address.
The service command is used to start - stop - and manage system services.
The lftp command can be used on a client to test FTP server connections.

47. What command do you use to change the permissions on a file or directory - To change ownership?
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 VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
The /etc/fstab file.
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.

48. The exportfs command is used to...
The du and df commands are used to view available space on the system.
rpcbind service
The -t nfs option is used with the mount command to mount NFS resources.
export one or all resources

49. What command can you use to validate the syntax of the Apache config 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.
You add your action to the end of the /home/user01/.bashrc file.
service httpd configtest
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.

50. What command can you use to change the context of files?
SELinux provides enhanced granular security for the Linux operating system.
browseable option
chcon
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.