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 and option do you use to view the description of Boolean values?
Use the ps command to view processes and their CPU usage.
getsebool -a | grep http
semanage boolean -l
atq

2. Can you name the two commands that can be used to view the free space on the system?
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
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.
The du and df commands are used to view available space on the system.
rpmbuild

3. How would you view all Boolean options for the HTTP service?
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 format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
getsebool -a | grep http

4. 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...

5. What command can you use to query information from the kernel about RAID arrays?
The /etc/fstab file.
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.
cat /proc/mdstat
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.

6. If you want a specific action to take place when user01 logs in to the system - which file would you edit?
Using the chcon command - you can change the context of a file to work with Apache.
The TFTP server uses UDP port 69.
You add your action to the end of the /home/user01/.bashrc file.
via the command line

7. What are SELinux Booleans?
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
SELinux Booleans provide restrictions to different aspects of a service.
The user_list file can be used to limit which users have access to the FTP server.
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514

8. What command can you use to test connectivity to another host?
DNS uses port 53.
The ping command can be used to verify connectivity to another host.
SELinux provides enhanced granular security for the Linux operating system.
The /var/log/audit/audit.log file contains all policy violations.

9. The old SysInit scripts have been replaced in Red Hat Enterprise Linux 6 for what new boot utility?
The tcpdump command is used to monitor network connections on different interfaces.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
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.
mkfs.ext4

10. 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.
The rpm command can operate in install - query - or verify modes.
The dig - host - and ping commands can be used to test DNS server functionality.

11. What is SSH used for?
Enforcing during installation
The /var/lib/nfs/etab file is used to keep track of currently exported resources.
A user's home directory is created under the /home directory.
SSH is used for secure remote management of Linux systems.

12. What does virsh reboot Client04 do?
This command reboots virtual guest Client04.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
chkconfig xinetd --list
VNC is used to control a remote desktop session.

13. What are the five required directories when building RPMS?
By defining a %post section - you can run scripts after a kickstart installation is complete.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
The service command is used to start - stop - and manage system services.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.

14. Samba servers can...
The lastlog and faillog commands are used to view user login-related events?
The user_list file can be used to limit which users have access to the FTP server.
serve both files and printers to users
alternatives --config mta

15. Which log file is used to keep track of policy violations?
have the same effect
Use the setgid flag to create the appropriate permissions (chmod 2770).
The /var/log/audit/audit.log file contains all policy violations.
export one or all resources

16. 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.
rpmbuild
Enforcing during installation
The smbstatus command shows you currently mounted Samba resources.
Physical volumes - volume groups - and logical volumes.

17. What command do you use to report information on quota usage?
repquota
SELinux Booleans provide restrictions to different aspects of a service.
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.

18. What command can you use to view system processes and their CPU usage?
Use the ps command to view processes and their CPU usage.
Use the yum groupinstall command to install multiple packages in a single group at once.
getsebool -a | grep http
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.

19. What port does the rndc utility listen on by default?
By default - the rndc utility listens on port 953.
user's home directory in the /etc/skel directory
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.
SSH is used for secure remote management of Linux systems.

20. What is the point of using SELinux?
createrepo
SELinux provides enhanced granular security for the Linux operating system.
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 web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.

21. What command is used to create an RPM package?
service httpd configtest
rpmbuild
mkfs.ext4
The dig - host - and ping commands can be used to test DNS server functionality.

22. How can you list all services on the system to tell whether they will boot during startup?
The vsftpd package is used to install an FTP server.
choose which mode you'd like it to operate in
The file system where quotas will be implemented must be mounted with the usrquota and grpquota options before quotas will work properly.
chkconfig—list

23. What option would you use to query an installed package using the rpm command?
used for kickstart and/or network installs
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 print option is used with both the fdisk and parted commands to display the current partition tables.
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.

24. What command can you use to get information about logical volumes?
The DHCP server listens on port 67 by default.
lvdisplay
LUKS encryption
The rdnc-confgen command generates an rndc.conf file for the rndc utility.

25. What command would you use to create a group - to add the user George to the group?
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
atq
The four types of DNS servers are master - slave - caching-only - and forwarding.

26. What are the side effects of shrinking a volume group or logical volume?
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.
Version 2 is the latest and most secure version of SSH.
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
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.

27. How can you check the currently mounted file systems?
have the same effect
The mount command lists all currently mounted file systems.
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
support TCP Wrappers

28. The portmap service was replaced by the ______________ in Red Hat Enterprise Linux 6.
rpcbind service
By defining a %post section - you can run scripts after a kickstart installation is complete.
DNS uses port 53.
Enforcing during installation

29. The firewall service is...
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.
enabled by default
useradd -c "Jr Admin" George
The htpasswd command can be used to password-protect a web page.

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

31. What three commands can you use to help verify that the DNS server is functioning properly?
The dig - host - and ping commands can be used to test DNS server functionality.
support TCP Wrappers
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
The ping command can be used to verify connectivity to another host.

32. What benefit does a web proxy provide to your network?
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 dig - host - and ping commands can be used to test DNS server functionality.
The nfsstat command can be used to view NFS statistics.
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.

33. What option needs to be used with the mount command to mount an NFS resource?
The -t nfs option is used with the mount command to mount NFS resources.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
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 you use to manage system services?
chcon
createrepo
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.

35. What is the main config file for the DHCP service?
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.
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.
getsebool

36. What command can you use to monitor and troubleshoot network connections?
The tcpdump command is used to monitor network connections on different interfaces.
used for kickstart and/or network installs
You can use the remove or erase options with yum to remove a package.
support for TCP Wrappers

37. What port must be opened on the firewall for DNS?
getsebool -a | grep http
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
DNS uses port 53.
SELinux provides enhanced granular security for the Linux operating system.

38. How would you disable SELinux protection for NFS - allowing shares to be read/write?
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
The virsh command is used to manage virtual guests.
generates errors under Red Hat Enterprise Linux 6
setsebool -P nfs_export_all_rw=1

39. What is NAT - How is it used?
Enforcing during installation
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.
By default - Squid runs on port 3128.
service httpd configtest

40. What command can you use to test the config files before starting the DNS service?
service named configtest
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
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
A virtual host is a way of hosting multiple sites using a single IP address.

41. To grow a file system
Use the resize2fs command to grow a file system.
The yum and rpm commands are used for package management.
getsebool
schedule one-time-only jobs

42. How can you verify the status of the SSH service after the system has booted?
service sshd statuts
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.
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.
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.

43. How can virtual hosts be used?
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 testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
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.
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.

44. What is VNC?
browseable option
VNC is used to control a remote desktop session.
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.
service dhcpd configtest

45. What is the difference between an A record and a PTR record?
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
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.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.

46. Can you name three utilities that can be used for network or DNS client troubleshooting?
The service command is used to start - stop - and manage system services.
The TFTP server uses UDP port 69.
The three utilities are: route - ping - and nslookup.
The ping command can be used to verify connectivity to another host.

47. What two ports should be opened on the firewall for the FTP server to function properly?
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
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
Sendmail
You must open TCP ports 20 and 21 for the FTP server to function properly.

48. Does a DHCP server allow reserved IP addresses - If so - how?
createrepo
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
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.

49. What port does the DHCP server listen on by default?
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
Kickstart supports both basic and advanced partitioning (RAID/LVM).
The DHCP server listens on port 67 by default.

50. What two commands are special for dealing with user login events?
By entering the GRUB boot menu - you can choose the a option to append something to the kernel command-line options.
The lastlog and faillog commands are used to view user login-related events?
A virtual host is a way of hosting multiple sites using a single IP address.
You must open TCP ports 20 and 21 for the FTP server to function properly.