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 client-side command can you use to test your FTP server connection?
halts the system
The lftp command can be used on a client to test FTP server connections.
Enforcing during installation
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.

2. How would you disable SELinux protection for NFS - allowing shares to be read/write?
setsebool -P nfs_export_all_rw=1
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.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
useradd -c "Jr Admin" George

3. It is possible to run scripts before a kickstart installation. This is done by...
By default - Squid runs on port 3128.
This chapter described tdbsm and smbpasswd back-end authentication.
defining a %pre section although it is rarely used
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.

4. What does the partprobe command do?
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
service httpd configtest
By default - Squid runs on port 3128.
The partprobe command forces the kernel to reread the partition table. You should always call it after making any changes to your system partitions.

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

6. 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).
DNS uses port 53.
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.
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.

7. The package selection screen allows you to install any software you want during the installation process as long as...
The smbpasswd command is used to create Samba users.
The vsftpd package is used to install an FTP server.
you have access to the correct packages or repositories.
chcon

8. What benefit does a web proxy provide to your network?
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
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 you connect to a hypervisor - you can use virsh list —all to list all virtual guests.

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

10. What is the name of the package that allows you to install VNC?
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).
choose which mode you'd like it to operate in
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.

11. You must dictate the ____________ you want allocated to your virtual machine when you create it.
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
Use the ps command to view processes and their CPU usage.
amount of RAM

12. What is the format of the /etc/shadow file?
semanage boolean -l
Physical volumes - volume groups - and logical volumes.
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
you have access to the correct packages or repositories.

13. The firewall service is...
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.
enabled by default
Sendmail
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.

14. What protocols are used with Dovecot?
you have access to the correct packages or repositories.
Dovecot supports the POP3 - POP3S - IMAP - and IMAPS protocols.
Kickstart supports both basic and advanced partitioning (RAID/LVM).
You add your action to the end of the /home/user01/.bashrc file.

15. What command can you use to query information from the kernel about RAID arrays?
cat /proc/mdstat
The smbstatus command shows you currently mounted Samba resources.
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.
The rpm command can operate in install - query - or verify modes.

16. How can virtual hosts be used?
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.
The print option is used with both the fdisk and parted commands to display the current partition tables.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.

17. 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.
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.
mkfs.ext4
Enforcing during installation
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.

18. What command-line program can you use to check your mail?
Physical volumes - volume groups - and logical volumes.
semanage boolean -l
The superblock is a structure that contains metadata of the file system. If this becomes corrupt - you are in trouble.
Typing the mail or mutt command allows you to read mail from the command line.

19. What is PAM used for?
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.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514
The virsh command is used to manage virtual guests.

20. What command can you use to view system processes and their CPU usage?
The nfsstat command can be used to view NFS statistics.
By default - Squid runs on port 3128.
Use the ps command to view processes and their CPU usage.
service httpd configtest

21. If you want a specific action to take place when user01 logs in to the system - which file would you edit?
For Apache to run a secure site - the mod_ssl package is required to be installed.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
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.
You add your action to the end of the /home/user01/.bashrc file.

22. What is a swap? Is it created as a partition or device file?
run on any port you'd like (provided that port is available)
The smbpasswd command is used to create Samba users.
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.
rpcbind service

23. Before you work with ACLs - what do you need to do to the file system?
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.
The file system where quotas will be implemented must be mounted with the usrquota and grpquota options before quotas will work properly.
Use the top command to view CPU and memory usage.

24. The portmap service was replaced by the ______________ in Red Hat Enterprise Linux 6.
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
rpcbind service
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
serve both files and printers to users

25. Which version of SSH should you use?
The /var/lib/nfs/etab file is used to keep track of currently exported resources.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.
Use the route command with the add option to create a static route.
Version 2 is the latest and most secure version of SSH.

26. What is the /etc/hosts file used for?

27. What command is used to create a user for Samba?
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 smbpasswd command is used to create Samba users.
halts the system
Use the setgid flag to create the appropriate permissions (chmod 2770).

28. What is the top command used for?
Use the top command to view CPU and memory usage.
For Apache to run a secure site - the mod_ssl package is required to be installed.
The DHCP server listens on port 67 by default.
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.

29. What three components are needed to fully automate a kickstart installation?
The last rule is always an implicit deny statement rejecting anything that wasn't matched by previous rules.
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.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
The lftp command can be used on a client to test FTP server connections.

30. What port does NFS use by default?
The htpasswd command can be used to password-protect a web page.
For Apache to run a secure site - the mod_ssl package is required to be installed.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.
The NFS service uses TCP port 2049 by default.

31. What is SSH used for?
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.
SELinux Booleans provide restrictions to different aspects of a service.
SSH is used for secure remote management of Linux systems.

32. What is the difference between an A record and a PTR record?
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.
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.
The dig - host - and ping commands can be used to test DNS server functionality.
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.

33. What option is used with both the fdisk and parted commands to display the current partition tables?
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.
Kickstart supports both basic and advanced partitioning (RAID/LVM).
The du and df commands are used to view available space on the system.
The print option is used with both the fdisk and parted commands to display the current partition tables.

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

35. How can you check the currently mounted file systems?
service sshd statuts
createrepo
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.
The mount command lists all currently mounted file systems.

36. What is a virtual host?
Uncomment the following line in the /etc/rsyslog.conf file: #$ModLoad imudp.so #$UDPServerRun 514
A virtual host is a way of hosting multiple sites using a single IP address.
amount of RAM
getsebool -a | grep http

37. What file is used to maintain custom parameters for the kernel during system boot?
The /etc/sysctl.conf file maintains a list of custom kernel parameters that should be applied during system boot.
The print option is used with both the fdisk and parted commands to display the current partition tables.
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.
chkconfig sshd off

38. What are the two config files for Postfix called?
chkconfig—list
The two main config files are master.cf and main.cf.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.
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.

39. What is the name of the section used to run scripts after a kickstart installation?
Use the ps command to view processes and their CPU usage.
By defining a %post section - you can run scripts after a kickstart installation is complete.
The tcpdump command is used to monitor network connections on different interfaces.
via the command line

40. What is 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.
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).
VNC is used to control a remote desktop session.
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.

41. What is the difference between the update (-U) and install (-i) options when using rpm to update the kernel?
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.
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.
For Apache to run a secure site - the mod_ssl package is required to be installed.
Apache uses port 80 for HTTP and port 443 for HTTPS.

42. What command can you use to create a new SSL certificate?
semanage boolean -l
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.
via the command line
user's home directory in the /etc/skel directory

43. What is a gateway used for on a network?
The two main config files are master.cf and main.cf.
Use the top command to view CPU and memory usage.
The anonymous_enable=YES option in the main config file allows anonymous uploads.
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.

44. What is the rndc utility used for?
The rndc utility provides a method for managing the DNS server remotely and securely.
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 rdnc-confgen command generates an rndc.conf file for the rndc utility.
chkconfig xinetd --list

45. What is the name of the package used to install an FTP?
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
DNS uses port 53.
The vsftpd package is used to install an FTP server.
user's home directory in the /etc/skel directory

46. FTP is one of three protocols ______________. The other two protocols are NFS and HTTP.
used for kickstart and/or network installs
Physical volumes - volume groups - and logical volumes.
load balancing and redundancy benefits
Use the route command with the add option to create a static route.

47. What command would you use to create a group - to add the user George to the group?
Use the groupadd command to create a group. You can then add user George with the following: usermod -G <group name> George
The virsh command is used to manage virtual guests.
Enforcing during installation
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.

48. What happens if you call the command from question 3 with the -c option after it has already been run?
The htpasswd command can be used to password-protect a web page.
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.
The smbstatus command shows you currently mounted Samba resources.
By default - the rndc utility listens on port 953.

49. What happens to jobs that are scheduled to run while the system is off?
service sshd statuts
The mount command lists all currently mounted file systems.
The file system where quotas will be implemented must be mounted with the usrquota and grpquota options before quotas 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.

50. What command can you use to create your own repositories?
setsebool -P nfs_export_all_rw=1
The /etc/fstab file.
createrepo
The file that stores usernames and their encrypted passwords is erased and replaced with a new file.