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 happens if you call the command from question 3 with the -c option after it has already been run?
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
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 file that stores usernames and their encrypted passwords is erased and replaced with a new file.
Enforcing during installation

2. The virt-install package allows you to manage virtual machines _____________. The virt-manager package allows you to manage virtual machines via a GUI interface.
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
The last rule is always an implicit deny statement rejecting anything that wasn't matched by previous rules.
via the command line
repquota

3. 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.
entering rescue mode and repairing the problem.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
mkfs.ext4

4. Runlevel 0 ___________. Runlevel 6 reboots the system.
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
halts the system
Network installations can be performed using the HTTP - FTP - and NFS protocols.
rpcbind service

5. The default SMTP service has been changed from _________ to Postfix in Red Hat Enterprise Linux 6.
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.
Sendmail
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
SELinux Booleans provide restrictions to different aspects of a service.

6. What command can you use to create a password-protected page?
The rndc utility provides a method for managing the DNS server remotely and securely.
Using the chcon command - you can change the context of a file to work with Apache.
The htpasswd command can be used to password-protect a web page.
run on any port you'd like (provided that port is available)

7. What does the testparm command do?
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
The TFTP server uses UDP port 69.

8. If a package is built on an RHEL6 system and deployed to a custom RHEL5 repository - are RHEL5 systems able to use it?
The /var/lib/nfs/etab file is used to keep track of currently exported resources.
you have access to the correct packages or repositories.
The du and df commands are used to view available space on the system.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.

9. What command can you use to test the config files before starting the DNS service?
By defining a %post section - you can run scripts after a kickstart installation is complete.
service named configtest
load balancing and redundancy benefits
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.

10. What command displays your current interfaces and IP address?
ifconfig
chkconfig sshd off
The gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
The three utilities are: route - ping - and nslookup.

11. What is the /etc/vsftpd/user_list file used for?
The user_list file can be used to limit which users have access to the FTP server.
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.
generates errors under Red Hat Enterprise Linux 6
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.

12. What command can you use to view NFS statistics?
createrepo
The nfsstat command can be used to view NFS statistics.
The du and df commands are used to view available space on the system.
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.

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

14. The old SysInit scripts have been replaced in Red Hat Enterprise Linux 6 for what new boot utility?
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
Typing the mail or mutt command allows you to read mail from the command line.
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.

15. The ____________ is available for each share.
The dig - host - and ping commands can be used to test DNS server functionality.
setsebool -P nfs_export_all_rw=1
chkconfig—list
browseable option

16. What command and options can you use to update the time?
enabled by default
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
The nfsstat command can be used to view NFS statistics.

17. What two ports should be opened on the firewall for the FTP server to function properly?
The three utilities are: route - ping - and nslookup.
Sendmail
cat /proc/mdstat
You must open TCP ports 20 and 21 for the FTP server to function properly.

18. What port does the SMTP service run on?
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.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
getsebool -a | grep http
The SMTP service runs on TCP port 110.

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

20. What are the five required directories when building RPMS?
The du and df commands are used to view available 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 two main config files are master.cf and main.cf.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.

21. What command can you use to view mounted Samba shares?
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.
service httpd configtest
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.
The smbstatus command shows you currently mounted Samba resources.

22. The at command is used to ____________. The cron service handles reoccurring system jobs.
enabled by default
The tcpdump command is used to monitor network connections on different interfaces.
schedule one-time-only jobs
cat /proc/mdstat

23. Samba servers can...
By default - the rndc utility listens on port 953.
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
serve both files and printers to users
A virtual host is a way of hosting multiple sites using a single IP address.

24. What command can you use to view the current ACL on a file?
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.
getfacl
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.
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.

25. What command can you use to change the context of files?
serve both files and printers to users
You can use the remove or erase options with yum to remove a package.
support TCP Wrappers
chcon

26. How can you check the currently mounted file systems?
You can use the remove or erase options with yum to remove a package.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.
The mount command lists all currently mounted file systems.
VNC is used to control a remote desktop session.

27. What are the three different types of RAID described in this chapter?
schedule one-time-only jobs
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
serve both files and printers to users
chcon

28. The package selection screen allows you to install any software you want during the installation process as long as...
user's home directory in the /etc/skel directory
The du and df commands are used to view available space on the system.
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
you have access to the correct packages or repositories.

29. What are the two config files for Postfix called?
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.
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.
A virtual host is a way of hosting multiple sites using a single IP address.
The two main config files are master.cf and main.cf.

30. What are the three items that make up LVM?
Network installations can be performed using the HTTP - FTP - and NFS protocols.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
Physical volumes - volume groups - and logical volumes.
DNS uses port 53.

31. What command would you use to create a group - to add the user George to the group?
The NFS service uses TCP port 2049 by default.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
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.

32. 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 yum and rpm commands are used for package management.
have the same effect
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 file that stores usernames and their encrypted passwords is erased and replaced with a new file.

33. Can you name the two commands that can be used to view the free space on the system?
The -t nfs option is used with the mount command to mount NFS resources.
The du and df commands are used to view available space on the system.
The DHCP server listens on port 67 by default.
cat /proc/mdstat

34. What two commands are special for dealing with user login events?
used for kickstart and/or network installs
The lastlog and faillog commands are used to view user login-related events?
Use the setgid flag to create the appropriate permissions (chmod 2770).
By default - the rndc utility listens on port 953.

35. How would you disable SELinux protection for NFS - allowing shares to be read/write?
run on any port you'd like (provided that port is available)
The DHCP server listens on port 67 by default.
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
setsebool -P nfs_export_all_rw=1

36. How can virtual hosts be used?
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 gateway is incorrectly set - and the subnet of the host you are trying to reach is inaccessible.
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.
serve both files and printers to users

37. What are the three modes in which the rpm command can operate?
The rpm command can operate in install - query - or verify modes.
The virsh command is used to manage virtual guests.
The ping command can be used to verify connectivity to another host.
You can use the authconfig-tui command or the authconfig command.

38. What command can you use to create a file system?
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.
mkfs.ext4
user's home directory in the /etc/skel directory

39. What is the rndc utility used for?
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
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 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.
The rndc utility provides a method for managing the DNS server remotely and securely.

40. What is the top command used for?
Use the top command to view CPU and memory usage.
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 /var/lib/nfs/etab file is used to keep track of currently exported resources.
The NFS service uses TCP port 2049 by default.

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

42. Before you work with quotas - what do you need to do to the file system?
The file system where quotas will be implemented must be mounted with the usrquota and grpquota options before quotas will work properly.
The DHCP server listens on port 67 by default.
You can use the authconfig-tui command or the authconfig command.
Version 2 is the latest and most secure version of SSH.

43. FTP is one of three protocols ______________. The other two protocols are NFS and HTTP.
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.
getfacl
used for kickstart and/or network installs
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.

44. 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 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.
browseable option
A virtual host is a way of hosting multiple sites using a single IP address.

45. To create a RAID or LVM partition using kickstart
Sendmail
Kickstart supports both basic and advanced partitioning (RAID/LVM).
getsebool
The rpm command can operate in install - query - or verify modes.

46. To grow a file system
The /var/lib/nfs/etab file is used to keep track of currently exported resources.
Use the resize2fs command to grow a file system.
A virtual host is a way of hosting multiple sites using a single IP address.
Use the top command to view CPU and memory usage.

47. Which file contains all messages generated during installation that can be used for troubleshooting if the need arises?
You add your action to the end of the /home/user01/.bashrc file.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
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.
getfacl

48. What two commands are used for package management?
Kickstart supports both basic and advanced partitioning (RAID/LVM).
The yum and rpm commands are used for package management.
VNC is used to control a remote desktop session.
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.

49. What is the point of using SELinux?
ifconfig
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.
SELinux provides enhanced granular security for the Linux operating system.
used for kickstart and/or network installs

50. What does virsh reboot Client04 do?
This command reboots virtual guest Client04.
The rndc utility provides a method for managing the DNS server remotely and securely.
getsebool -a | grep http
generates errors under Red Hat Enterprise Linux 6