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 rndc utility listen on by default?
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.
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.
By default - the rndc utility listens on port 953.
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.

2. What command (and options) can be used to create a user named George with the description "Jr Admin"?
useradd -c "Jr Admin" George
serve both files and printers to users
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
halts the system

3. Where are Yum repository config files located?
getfacl
lvdisplay
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.
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.

4. To create a RAID or LVM partition using kickstart
Typing the mail or mutt command allows you to read mail from the command line.
rpmbuild
Kickstart supports both basic and advanced partitioning (RAID/LVM).
The lastlog and faillog commands are used to view user login-related events?

5. A PXE server eases the automation process but isn't required for...
kickstart installations to work
The lftp command can be used on a client to test FTP server connections.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.

6. What are the three different types of RAID described in this chapter?
The htpasswd command can be used to password-protect a web page.
The two main config files are master.cf and main.cf.
atq
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).

7. What is the name of the package used to install an FTP?
alternatives --config mta
The three utilities are: route - ping - and nslookup.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
The vsftpd package is used to install an FTP server.

8. What file needs to be edited so that the system will mount a file system at boot time?
The /etc/fstab file.
chkconfig—list
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
LUKS encryption

9. What command can be used to easily list all the options in the FTP main config file?
setsebool -P nfs_export_all_rw=1
cat /proc/mdstat
enabled by default
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.

10. What directory is used to represent the virtual file system created by the kernel?
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
This command reboots virtual guest Client04.
The user_list file can be used to limit which users have access to the FTP server.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.

11. What command can you use to view NFS statistics?
The nfsstat command can be used to view NFS statistics.
The lftp command can be used on a client to test FTP server connections.
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.
browseable option

12. What does S12rsyslog in the /etc/rc.d/rc2.d directory mean?
VNC is used to control a remote desktop session.
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
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.
have the same effect

13. What is the superblock used for?
useradd -c "Jr Admin" George
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
service dhcpd configtest
The virsh command is used to manage virtual guests.

14. What is the benefit to using centralized authentication?

15. 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.
Enforcing during installation
The three utilities are: route - ping - and nslookup.
By default - the rndc utility listens on port 953.
The virsh command is used to manage virtual guests.

16. What option is used to allow anonymous uploads to the FTP server?
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
The anonymous_enable=YES option in the main config file allows anonymous uploads.
The htpasswd command can be used to password-protect a web page.
serve both files and printers to users

17. What command can you use to create your own repositories?
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.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
service sshd statuts
createrepo

18. Which version of SSH should you use?
Version 2 is the latest and most secure version of SSH.
The rdnc-confgen command generates an rndc.conf file for the rndc utility.
Use the ps command to view processes and their CPU usage.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.

19. Which remote management service is installed by default?Can you name the port that it uses?
The /var/log/audit/audit.log file contains all policy violations.
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 VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
The user_list file can be used to limit which users have access to the FTP server.

20. It is possible to run scripts before a kickstart installation. This is done by...
defining a %pre section although it is rarely used
The anonymous_enable=YES option in the main config file allows anonymous uploads.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
service named configtest

21. The ______________ for Red Hat Enterprise Linux 5 or 6 includes the use of LVM.
Enforcing during installation
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/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
The SMTP service runs on TCP port 110.

22. What option needs to be used with the mount command to mount an NFS resource?
By default - Squid runs on port 3128.
getsebool
Sendmail
The -t nfs option is used with the mount command to mount NFS resources.

23. A slave DNS server provides...
You must open TCP ports 20 and 21 for the FTP server to function properly.
Enforcing during installation
SELinux Booleans provide restrictions to different aspects of a service.
load balancing and redundancy benefits

24. What option would you use to query an installed package using the rpm command?
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.
Use the top command to view CPU and memory usage.
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.
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.

25. What does ifconfig 172.168.1.100 netmask 255.255.255.0 eth1 do?
The last rule is always an implicit deny statement rejecting anything that wasn't matched by previous rules.
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 file system where quotas will be implemented must be mounted with the usrquota and grpquota options before quotas will work properly.
The htpasswd command can be used to password-protect a web page.

26. What does the following firewall rule accomplish: iptables -I INPUT 5 -p tcp -m tcp --dport 80 -j ACCEPT?
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 /var/lib/nfs/etab file is used to keep track of currently exported resources.
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.

27. What is the top command used for?
You add your action to the end of the /home/user01/.bashrc file.
Use the setgid flag to create the appropriate permissions (chmod 2770).
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
Use the top command to view CPU and memory usage.

28. The ____________ is available for each share.
SSH is used for secure remote management of Linux systems.
SELinux provides enhanced granular security for the Linux operating system.
chkconfig sshd off
browseable option

29. If you want a specific action to take place when user01 logs in to the system - which file would you edit?
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
You add your action to the end of the /home/user01/.bashrc file.
The four types of DNS servers are master - slave - caching-only - and forwarding.
Enforcing during installation

30. 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.
The vsftpd package is used to install an FTP server.
Typing the mail or mutt command allows you to read mail from the command line.
chkconfig sshd off

31. Are additional packages besides httpd required for a secure website - If so - what are they?
For Apache to run a secure site - the mod_ssl package is required to be installed.
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.
service httpd configtest
Use the route command with the add option to create a static route.

32. What command can you use to query information from the kernel about RAID arrays?
cat /proc/mdstat
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
rpmbuild
The service command is used to start - stop - and manage system services.

33. What is a gateway used for on a network?
The lftp command can be used on a client to test FTP server connections.
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 nfsstat command can be used to view NFS statistics.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.

34. 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...

35. What is the virsh command used for?
The two main config files are master.cf and main.cf.
The virsh command is used to manage virtual guests.
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.
By default - the rndc utility listens on port 953.

36. What command would you use to create a group - to add the user George to the group?
Use the setgid flag to create the appropriate permissions (chmod 2770).
getsebool
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
load balancing and redundancy benefits

37. The default SMTP service has been changed from _________ to Postfix in Red Hat Enterprise Linux 6.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
Sendmail
ifconfig
generates errors under Red Hat Enterprise Linux 6

38. What are the five required directories when building RPMS?
The smbstatus command shows you currently mounted Samba resources.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
Use the top command to view CPU and memory usage.
useradd -c "Jr Admin" George

39. Does a DHCP server allow reserved IP addresses - If so - how?
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
amount of RAM
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.

40. Explain the difference between soft and hard limits in quotas.

41. What is the /var/lib/nfs/etab file used for?
Version 2 is the latest and most secure version of SSH.
The /var/lib/nfs/etab file is used to keep track of currently exported resources.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
You can use the remove or erase options with yum to remove a package.

42. What is the last rule in the iptables file?

43. To grow a file system
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 SMTP service runs on TCP port 110.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
Use the resize2fs command to grow a file system.

44. What does virsh reboot Client04 do?
support TCP Wrappers
defining a %pre section although it is rarely used
The four types of DNS servers are master - slave - caching-only - and forwarding.
This command reboots virtual guest Client04.

45. What port does the DHCP server listen on by default?
used for kickstart and/or network installs
The lftp command can be used on a client to test FTP server connections.
By default - the rndc utility listens on port 953.
The DHCP server listens on port 67 by default.

46. Can you name three utilities that can be used for network or DNS client troubleshooting?
The three utilities are: route - ping - and nslookup.
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
Apache uses port 80 for HTTP and port 443 for HTTPS.
chkconfig—list

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

48. What does the testparm command do?
The NFS service uses TCP port 2049 by default.
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
You can use the remove or erase options with yum to remove a package.
The rdnc-confgen command generates an rndc.conf file for the rndc utility.

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

50. A service needs to have _______________ to be able to use it.
The xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
support for TCP Wrappers
service named configtest
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.