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 virsh command used for?
By default - the rndc utility listens on port 953.
enabled by default
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
The virsh command is used to manage virtual guests.

2. What option would you use to query an installed package using the rpm command?
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.
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.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
repquota

3. What are the three items that make up LVM?
Physical volumes - volume groups - and logical volumes.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
getsebool
By default - Squid runs on port 3128.

4. FTP is one of three protocols ______________. The other two protocols are NFS and HTTP.
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.
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.
used for kickstart and/or network installs
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.

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

6. How can you list all services on the system to tell whether they will boot during startup?
Network installations can be performed using the HTTP - FTP - and NFS protocols.
halts the system
chkconfig—list
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.

7. Can you put your /boot partition on a RAID 5 array?
Use the top command to view CPU and memory usage.
entering rescue mode and repairing the problem.
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.
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.

8. What is the name of the section used to run scripts after a kickstart installation?
By default - the rndc utility listens on port 953.
service sshd statuts
By defining a %post section - you can run scripts after a kickstart installation is complete.
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.

9. What command can you use to check the config file of the DHCP server?
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
A user's home directory is created under the /home directory.
service dhcpd configtest
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514

10. Which remote management service is installed by default?Can you name the port that it uses?
VNC is used to control a remote desktop session.
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.
The tcpdump command is used to monitor network connections on different interfaces.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.

11. What command can be used to view the queue for at service jobs?
rpmbuild
This command reboots virtual guest Client04.
atq
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.

12. How would you install a group of packages all at a single time?
The ping command can be used to verify connectivity to another host.
A user's home directory is created under the /home directory.
Use the yum groupinstall command to install multiple packages in a single group at once.
chkconfig—list

13. How would you disable SELinux protection for NFS - allowing shares to be read/write?
rpcbind service
setsebool -P nfs_export_all_rw=1
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
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.

14. What command can you use to query Boolean values?
getsebool
The SMTP service runs on TCP port 110.
enabled by default
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.

15. You must dictate the ____________ you want allocated to your virtual machine when you create it.
amount of RAM
generates errors under Red Hat Enterprise Linux 6
This command reboots virtual guest Client04.
Version 2 is the latest and most secure version of SSH.

16. What command and option do you use to view the description of Boolean values?
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
Enforcing during installation
semanage boolean -l

17. What command can you use to get information about logical volumes?
amount of RAM
lvdisplay
Enforcing during installation
The print option is used with both the fdisk and parted commands to display the current partition tables.

18. How can virtual hosts be used?
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.
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.
amount of RAM
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.

19. What command can you use to change the context of files?
chkconfig xinetd --list
chcon
The du and df commands are used to view available space 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.

20. Which file shows you all the client IP addresses?
You must open TCP ports 20 and 21 for the FTP server to function properly.
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
By default - Squid runs on port 3128.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.

21. What is a swap? Is it created as a partition or device file?
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
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 -t nfs option is used with the mount command to mount NFS resources.

22. The virt-install package allows you to manage virtual machines _____________. The virt-manager package allows you to manage virtual machines via a GUI interface.
Sendmail
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
The user_list file can be used to limit which users have access to the FTP server.
via the command line

23. Where are Yum repository config files located?
Enforcing during installation
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
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.
The service command is used to start - stop - and manage system services.

24. A service needs to have _______________ to be able to use it.
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
support for TCP Wrappers
The user_list file can be used to limit which users have access to the FTP server.
The service command is used to start - stop - and manage system services.

25. 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 resize2fs command to grow a file system.
Typing the mail or mutt command allows you to read mail from the command line.
The rndc utility provides a method for managing the DNS server remotely and securely.

26. What two ports should be opened on the firewall for the FTP server to function properly?
The TFTP server uses UDP port 69.
halts the system
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
You must open TCP ports 20 and 21 for the FTP server to function properly.

27. If a package is built on an RHEL6 system and deployed to a custom RHEL5 repository - are RHEL5 systems able to use it?
repquota
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
getsebool -a | grep http

28. Most boot issues can be resolved by...
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
The anonymous_enable=YES option in the main config file allows anonymous uploads.
entering rescue mode and repairing the problem.
service httpd configtest

29. What command can you use to manage system services?
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 service command is used to start - stop - and manage system services.
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 rpm command can operate in install - query - or verify modes.

30. What is the name of the package that allows you to install VNC?
The user_list file can be used to limit which users have access to the FTP server.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
generates errors under Red Hat Enterprise Linux 6
The /var/lib/nfs/etab file is used to keep track of currently exported resources.

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

32. What command and option can you use to enable a service to start on boot?
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
generates errors under Red Hat Enterprise Linux 6
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.

33. 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 rdnc-confgen command generates an rndc.conf file for the rndc utility.
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.

34. Red Hat Enterprise Linux 6 is the only version that officially supports _______
LUKS encryption
The ping command can be used to verify connectivity to another host.
The SMTP service runs on TCP port 110.
kickstart installations to work

35. How can you display all virtual guests after they're connected to a hypervisor?
VNC is used to control a remote desktop session.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
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 grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.

36. What is the difference between an A record and a PTR record?
You add your action to the end of the /home/user01/.bashrc file.
rpmbuild
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
SELinux Booleans provide restrictions to different aspects of a service.

37. How would you view all Boolean options for the HTTP service?
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
getsebool -a | grep http
via the command line
entering rescue mode and repairing the problem.

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

39. Do you need to write changes to the disk when using the parted command? What about fdisk?
ifconfig
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.
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 DHCP server listens on port 67 by default.

40. Before you work with ACLs - what do you need to do to the file system?
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
Kickstart supports both basic and advanced partitioning (RAID/LVM).
VNC is used to control a remote desktop session.
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.

41. What three commands can you use to help verify that the DNS server is functioning properly?
You must open TCP ports 20 and 21 for the FTP server to function properly.
The dig - host - and ping commands can be used to test DNS server functionality.
Enforcing during installation
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.

42. What command can be used to easily list all the options in the FTP main config file?
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.
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.

43. What port does the SMTP service run on?
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
The SMTP service runs on TCP port 110.
Physical volumes - volume groups - and logical volumes.
SELinux provides enhanced granular security for the Linux operating system.

44. What does it mean if you ping a host and you receive the response Destination Unreachable?
Use the setgid flag to create the appropriate permissions (chmod 2770).
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
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 TFTP server uses UDP port 69.

45. How would you go about creating a static route?
A user's home directory is created under the /home directory.
The user_list file can be used to limit which users have access to the FTP server.
Use the route command with the add option to create a static route.
halts the system

46. What commands can you use to add a client machine to an LDAP server?
Use the ps command to view processes and their CPU usage.
You can use the authconfig-tui command or the authconfig command.
Network installations can be performed using the HTTP - FTP - and NFS protocols.
Apache uses port 80 for HTTP and port 443 for HTTPS.

47. What protocols are used with Dovecot?
support for TCP Wrappers
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.

48. What is the rndc utility used for?
The rndc utility provides a method for managing the DNS server remotely and securely.
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.
alternatives --config mta
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.

49. What options with the yum command would you use to remove a package?
useradd -c "Jr Admin" George
Use the resize2fs command to grow a file system.
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.
You can use the remove or erase options with yum to remove a package.

50. The ____________ is available for each share.
Using the chcon command - you can change the context of a file to work with Apache.
browseable option
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.
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.