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. Where are Yum repository config files located?
The anonymous_enable=YES option in the main config file allows anonymous uploads.
By default - the rndc utility listens on port 953.
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.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.

2. 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...

3. Which remote management service is installed by default?Can you name the port that it uses?
atq
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 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.
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.

4. What is NAT - How is it used?
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
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.
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 -t nfs option is used with the mount command to mount NFS resources.

5. Are additional packages besides httpd required for a secure website - If so - what are they?
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.
atq
service named configtest
For Apache to run a secure site - the mod_ssl package is required to be installed.

6. FTP is one of three protocols ______________. The other two protocols are NFS and HTTP.
Use the ps command to view processes and their CPU usage.
used for kickstart and/or network installs
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
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.

7. 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...
The rpm command can operate in install - query - or verify modes.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
chkconfig sshd off
have the same effect

8. What option is used with both the fdisk and parted commands to display the current partition tables?
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
The print option is used with both the fdisk and parted commands to display the current partition tables.
The service command is used to start - stop - and manage system services.
A virtual host is a way of hosting multiple sites using a single IP address.

9. What command can you use to create a file system?
The rndc utility provides a method for managing the DNS server remotely and securely.
mkfs.ext4
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.
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

10. Which file shows you all the client IP addresses?
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
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.

11. What is the format of the /etc/shadow file?
The service command is used to start - stop - and manage system services.
rpcbind service
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.

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

13. SSH does...
The anonymous_enable=YES option in the main config file allows anonymous uploads.
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
The TFTP server uses UDP port 69.
support TCP Wrappers

14. What is the top command used for?
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
mkfs.ext4
Use the top command to view CPU and memory usage.
DNS uses port 53.

15. How can you list all services on the system to tell whether they will boot during startup?
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
chkconfig—list
getfacl
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.

16. 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.
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.
The du and df commands are used to view available space on the system.
Use the route command with the add option to create a static route.

17. How can virtual hosts be used?
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.
The yum and rpm commands are used for package management.
A virtual host is a way of hosting multiple sites using a single IP address.
via the command line

18. The old SysInit scripts have been replaced in Red Hat Enterprise Linux 6 for what new boot utility?
SELinux provides enhanced granular security for the Linux operating system.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
Sendmail
The smbstatus command shows you currently mounted Samba resources.

19. What command can you use to change the context of files?
repquota
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
This chapter described tdbsm and smbpasswd back-end authentication.
chcon

20. What option at the GRUB boot menu can you use to append something to a kernel?
getsebool -a | grep http
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
The mount command lists all currently mounted file systems.
The -t nfs option is used with the mount command to mount NFS resources.

21. What happens to jobs that are scheduled to run while the system is off?
chkconfig sshd off
The /var/log/audit/audit.log file contains all policy violations.
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.
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.

22. If a package is built on an RHEL6 system and deployed to a custom RHEL5 repository - are RHEL5 systems able to use it?
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
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
Use the ps command to view processes and their CPU usage.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.

23. To create a RAID or LVM partition using kickstart
generates errors under Red Hat Enterprise Linux 6
SELinux Booleans provide restrictions to different aspects of a service.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
Kickstart supports both basic and advanced partitioning (RAID/LVM).

24. How can you change the security context of a directory to work with Apache?
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
Using the chcon command - you can change the context of a file to work with Apache.
halts the system
Version 2 is the latest and most secure version of SSH.

25. What is the xinetd service used for?
Use the ps command to view processes and their CPU usage.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
chkconfig xinetd --list
service dhcpd configtest

26. What command can you use to view NFS statistics?
The nfsstat command can be used to view NFS statistics.
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.
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.
createrepo

27. What two ports should be opened on the firewall for the FTP server to function properly?
You must open TCP ports 20 and 21 for the FTP server to function properly.
Use the resize2fs command to grow a file system.
chkconfig—list
The nfsstat command can be used to view NFS statistics.

28. How can you verify the status of the SSH service after the system has booted?
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.
service sshd statuts
Use the top command to view CPU and memory usage.
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.

29. It is possible to run scripts before a kickstart installation. This is done by...
setsebool -P nfs_export_all_rw=1
defining a %pre section although it is rarely used
By default - Squid runs on port 3128.
support TCP Wrappers

30. What option needs to be used with the mount command to mount an NFS resource?
amount of RAM
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 -t nfs option is used with the mount command to mount NFS 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.

31. GRUB has three stages. Can you name them?
VNC is used to control a remote desktop session.
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 named configtest
via the command line

32. What command can you use to create a new SSL certificate?
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 /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
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.

33. Can you name the two commands that can be used to view the free space on the 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.
The du and df commands are used to view available space on the system.
user's home directory in the /etc/skel directory
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.

34. What does the following firewall rule accomplish: iptables -I INPUT 5 -p tcp -m tcp --dport 80 -j ACCEPT?
Use the setgid flag to create the appropriate permissions (chmod 2770).
This command reboots virtual guest Client04.
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 -t nfs option is used with the mount command to mount NFS resources.

35. What port does the DHCP server listen on by default?
The service command is used to start - stop - and manage system services.
The DHCP server listens on port 67 by default.
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.

36. 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.
createrepo
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.
Network installations can be performed using the HTTP - FTP - and NFS protocols.

37. If you want a specific action to take place when user01 logs in to the system - which file would you edit?
You add your action to the end of the /home/user01/.bashrc file.
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.
setsebool -P nfs_export_all_rw=1
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514

38. What command disables the SSH service from running when the system boots?
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.
service named configtest
choose which mode you'd like it to operate in
chkconfig sshd off

39. Runlevel 0 ___________. Runlevel 6 reboots the system.
createrepo
halts the system
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 print option is used with both the fdisk and parted commands to display the current partition tables.

40. The ____________ is available for each share.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
The tcpdump command is used to monitor network connections on different interfaces.
The htpasswd command can be used to password-protect a web page.
browseable option

41. Red Hat Enterprise Linux 6 is the only version that officially supports _______
LUKS encryption
Using the chcon command - you can change the context of a file to work with Apache.
serve both files and printers to users
chcon

42. What option would you use to query an installed package using the rpm command?
enabled by default
The smbpasswd command is used to create Samba users.
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 virsh command is used to manage virtual guests.

43. Before you work with ACLs - what do you need to do to the file system?
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.
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 gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.

44. Which log file is used to keep track of policy violations?
useradd -c "Jr Admin" George
The /var/log/audit/audit.log file contains all policy violations.
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.
Using the chcon command - you can change the context of a file to work with Apache.

45. Which file contains all messages generated during installation that can be used for troubleshooting if the need arises?
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.
Using the chcon command - you can change the context of a file to work with Apache.
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.

46. What is the /etc/vsftpd/user_list file used for?
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 user_list file can be used to limit which users have access to the FTP server.
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
Use the resize2fs command to grow a file system.

47. What is a swap? Is it created as a partition or device file?
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514
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.
By defining a %post section - you can run scripts after a kickstart installation is complete.
The /var/lib/nfs/etab file is used to keep track of currently exported resources.

48. What command can you use to monitor and troubleshoot network connections?
The tcpdump command is used to monitor network connections on different interfaces.
Use the setgid flag to create the appropriate permissions (chmod 2770).
The /var/log/audit/audit.log file contains all policy violations.
enabled by default

49. What command is used to create an RPM package?
rpmbuild
The /var/lib/nfs/etab file is used to keep track of currently exported resources.
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
service sshd statuts

50. What directory is used to represent the virtual file system created by the kernel?
service httpd configtest
kickstart installations to work
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.
defining a %pre section although it is rarely used