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. How can you check the currently mounted file systems?
Apache uses port 80 for HTTP and port 443 for HTTPS.
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
The mount command lists all currently mounted file systems.
The rdnc-confgen command generates an rndc.conf file for the rndc utility.

2. What is the top command used for?
amount of RAM
The NFS service uses TCP port 2049 by default.
Use the top command to view CPU and memory usage.
cat /proc/mdstat

3. What command can you use to query Boolean values?
getsebool
The service command is used to start - stop - and manage system services.
Use the resize2fs command to grow a file system.
The mount command lists all currently mounted file systems.

4. What are the five required directories when building RPMS?
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.
The -t nfs option is used with the mount command to mount NFS resources.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.

5. What command can you use to get information about logical volumes?
lvdisplay
chcon
Use the setgid flag to create the appropriate permissions (chmod 2770).
Use the resize2fs command to grow a file system.

6. How can you verify the status of the SSH service after the system has booted?
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
service sshd statuts
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.
Kickstart supports both basic and advanced partitioning (RAID/LVM).

7. Which version of SSH should you use?
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
defining a %pre section although it is rarely used
choose which mode you'd like it to operate in
Version 2 is the latest and most secure version of SSH.

8. What command can be used to view the queue for at service jobs?
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
Use the yum groupinstall command to install multiple packages in a single group at once.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
atq

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

10. How would you go about creating a static route?
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.
Use the resize2fs command to grow a file system.
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.
Use the route command with the add option to create a static route.

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

12. What does the testparm command do?
atq
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).
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.

13. What does the rdnc-confgen command do?
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.
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
The three utilities are: route - ping - and nslookup.

14. What command can you use to test the config files before starting the DNS service?
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.
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
service named configtest

15. What does S12rsyslog in the /etc/rc.d/rc2.d directory mean?
rpcbind service
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.
used for kickstart and/or network installs
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.

16. 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.
rpcbind service
lvdisplay
have the same effect

17. What port does the Apache web server run on - What about HTTPS?
support for TCP Wrappers
The DHCP server listens on port 67 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
Apache uses port 80 for HTTP and port 443 for HTTPS.

18. What command is used to create a user for Samba?
chkconfig sshd off
The smbpasswd command is used to create Samba users.
support TCP Wrappers
chcon

19. What is SSH used for?
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
user's home directory in the /etc/skel directory
SSH is used for secure remote management of Linux systems.
The file system where quotas will be implemented must be mounted with the usrquota and grpquota options before quotas will work properly.

20. What is the benefit to using centralized authentication?

21. How would you install a group of packages all at a single time?
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.
Use the yum groupinstall command to install multiple packages in a single group at once.
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.
The /etc/fstab file.

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

23. What three commands can you use to help verify that the DNS server is functioning properly?
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
The dig - host - and ping commands can be used to test DNS server functionality.
The service command is used to start - stop - and manage system services.

24. What three protocols can you use to perform network installations?
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.
entering rescue mode and repairing the problem.
Network installations can be performed using the HTTP - FTP - and NFS protocols.
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.

25. What option can you change in the rsyslog config file to accept remote logs (acting as a centralized logging server)?
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514
getsebool -a | grep http
The user_list file can be used to limit which users have access to the FTP 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.

26. Which remote management service is installed by default?Can you name the port that it uses?
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 partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
The two main config files are master.cf and main.cf.
service dhcpd configtest

27. 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.
getsebool -a | grep http
The du and df commands are used to view available space on the system.
support TCP Wrappers

28. What port does the SMTP service run on?
The TFTP server uses UDP port 69.
The SMTP service runs on TCP port 110.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
service httpd configtest

29. GRUB has three stages. Can you name them?
setsebool -P nfs_export_all_rw=1
kickstart installations to work
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
SELinux provides enhanced granular security for the Linux operating system.

30. What command can you use to validate the syntax of the Apache config file?
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
For Apache to run a secure site - the mod_ssl package is required to be installed.
service httpd configtest
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.

31. A service needs to have _______________ to be able to use it.
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
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 testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
support for TCP Wrappers

32. Is it possible to share files among groups - What permissions would you set on the directory to accomplish file sharing if possible?
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 rpm command can operate in install - query - or verify modes.
Use the setgid flag to create the appropriate permissions (chmod 2770).
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. There are four types of DNS servers. Name them.
The /var/log/audit/audit.log file contains all policy violations.
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.
service sshd statuts
The four types of DNS servers are master - slave - caching-only - and forwarding.

34. What are SELinux Booleans?
The smbstatus command shows you currently mounted Samba resources.
By defining a %post section - you can run scripts after a kickstart installation is complete.
SELinux Booleans provide restrictions to different aspects of a service.
The yum and rpm commands are used for package management.

35. How do you run a command with elevated privileges?
The rndc utility provides a method for managing the DNS server remotely and securely.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
The service command is used to start - stop - and manage system services.
enabled by default

36. Which log file is used to keep track of policy violations?
run on any port you'd like (provided that port is available)
The mount command lists all currently mounted file systems.
The /var/log/audit/audit.log file contains all policy violations.
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.

37. A PXE server eases the automation process but isn't required for...
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.
kickstart installations to work
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
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.

38. What is a gateway used for on a network?
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 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.
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.
Physical volumes - volume groups - and logical volumes.

39. What client-side command can you use to test your FTP server connection?
enabled by default
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.
Physical volumes - volume groups - and logical volumes.
The lftp command can be used on a client to test FTP server connections.

40. What command can you use to view mounted Samba shares?
The smbstatus command shows you currently mounted Samba resources.
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
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 /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.

41. What command can you use to create a new SSL certificate?
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
Sendmail

42. What is the virsh command used for?
The two main config files are master.cf and main.cf.
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.
The virsh command is used to manage virtual guests.
The /etc/fstab file.

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

44. 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 virsh command is used to manage virtual guests.
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
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.

45. What file needs to be edited so that the system will mount a file system at boot time?
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
The yum and rpm commands are used for package management.
The /etc/fstab file.
Use the setgid flag to create the appropriate permissions (chmod 2770).

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

47. What is the name of the package that allows you to install VNC?
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
The last rule is always an implicit deny statement rejecting anything that wasn't matched by previous rules.
halts the system
rpmbuild

48. What command would you use to create a group - to add the user George to the group?
enabled by default
This chapter described tdbsm and smbpasswd back-end authentication.
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
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.

49. What are the two config files for Postfix called?
The smbpasswd command is used to create Samba users.
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 two main config files are master.cf and main.cf.
Use the yum groupinstall command to install multiple packages in a single group at once.

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