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. Does a DHCP server allow reserved IP addresses - If so - how?
The NFS service uses TCP port 2049 by default.
Using the host option in the dhcpd.conf file allows you to reserve a client IP address based on its MAC address.
The VNC package for Red Hat Enterprise Linux 6 is tiger-vnc.
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

2. 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.
amount of RAM
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.
Use the chkconfig command to enable or disable services during the boot process. The on option enables the service and off disables it.

3. What is the point of using SELinux?
The htpasswd command can be used to password-protect a web page.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
SELinux provides enhanced granular security for the Linux operating system.
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.

4. What port does the rndc utility listen on by default?
Use the resize2fs command to grow a file system.
By default - the rndc utility listens on port 953.
load balancing and redundancy benefits
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.

5. What command can you use to manage system services?
The rndc utility provides a method for managing the DNS server remotely and securely.
support for TCP Wrappers
The service command is used to start - stop - and manage system services.
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.

6. What is a virtual host?
enabled by default
By defining a %post section - you can run scripts after a kickstart installation is complete.
A virtual host is a way of hosting multiple sites using a single IP address.
Use the yum groupinstall command to install multiple packages in a single group at once.

7. What command can you use to monitor and troubleshoot network connections?
The tcpdump command is used to monitor network connections on different interfaces.
export one or all resources
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
The nfsstat command can be used to view NFS statistics.

8. What command displays your current interfaces and IP address?
getsebool -a | grep http
ifconfig
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.
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.

9. Where are Yum repository config files located?
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.
useradd -c "Jr Admin" George
The /etc/hosts file is a local lookup file used to map IP addresses to hostnames if a DNS server isn't available.
This command reboots virtual guest Client04.

10. What port must be opened on the firewall for DNS?
The htpasswd command can be used to password-protect a web page.
DNS uses port 53.
user's home directory in the /etc/skel directory
The smbpasswd command is used to create Samba users.

11. What command can you use to test connectivity to another host?
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 ping command can be used to verify connectivity to another host.
The /etc/dhcp/dhcpd.conf file is the main config file for the DHCP service.
An ext3 file system has journaling built in to it - whereas the ext2 file system doesn't.

12. The at command is used to ____________. The cron service handles reoccurring system jobs.
By default - Squid runs on port 3128.
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.
schedule one-time-only jobs
The rdnc-confgen command generates an rndc.conf file for the rndc utility.

13. What is NAT - How is it used?
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
The last rule is always an implicit deny statement rejecting anything that wasn't matched by previous rules.
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.
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.

14. What command can you use to validate the syntax of the Apache config file?
The print option is used with both the fdisk and parted commands to display the current partition tables.
service httpd configtest
The user_list file can be used to limit which users have access to the FTP server.
Use the setgid flag to create the appropriate permissions (chmod 2770).

15. What is a gateway used for on a network?
Use the top command to view CPU and memory usage.
chcon
A user's home directory is created under the /home 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.

16. What is PAM used for?
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.
kickstart installations to work
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.
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.

17. What are the three different types of RAID described in this chapter?
amount of RAM
LUKS encryption
The yum and rpm commands are used for package management.
RAID 0 (Striping) - RAID 1 (Mirror) - and RAID 5 (Striping with parity).

18. What is the format of the /etc/shadow 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.
After you connect to a hypervisor - you can use virsh list —all to list all virtual guests.
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.

19. What two commands are special for dealing with user login events?
schedule one-time-only jobs
The lastlog and faillog commands are used to view user login-related events?
An A record translates translated hostnames to IP addresses - and a PTR record works the other way around.
export one or all resources

20. What command and options can you use to update the time?
kickstart installations to work
lvdisplay
After the ntpd service is stopped - you can use the ntpdate <server> command to update/sync the time.
You can use the sudo command to run a command with elevated privileges provided you have the rights in the /etc/sudoers file.

21. What three protocols can you use to perform network installations?
choose which mode you'd like it to operate in
Network installations can be performed using the HTTP - FTP - and NFS protocols.
The user_list file can be used to limit which users have access to the FTP server.
The anonymous_enable=YES option in the main config file allows anonymous uploads.

22. What is the difference between an ext2 and ext3 file system?

23. If a package is built on an RHEL6 system and deployed to a custom RHEL5 repository - are RHEL5 systems able to use it?
No. Red Hat Enterprise Linux 6 uses a different key to sign its packages.
useradd -c "Jr Admin" George
The NFS service uses TCP port 2049 by default.
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

24. What command can you use to change the context of files?
chcon
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 must open TCP ports 20 and 21 for the FTP server to function properly.
Use the top command to view CPU and memory usage.

25. What are the three modes in which the rpm command can operate?
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 rpm command can operate in install - query - or verify modes.
The ping command can be used to verify connectivity to another host.
The lastlog and faillog commands are used to view user login-related events?

26. What critical step must you take after updating the kernel to a newer version?
service named configtest
browseable option
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.
By default - the rndc utility listens on port 953.

27. What command is used to show all services being controlled by the xinetd daemon?
semanage boolean -l
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.
The /etc/fstab file.
chkconfig xinetd --list

28. What command can you use to create a new SSL certificate?
The grep -v ^# /etc/vsftpd/vsftpd.conf command shows you all the options currently being used with the FTP server.
The /proc directory. The /proc/sys directory is the place where you actually tune kernel parameters.
enabled by default
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.

29. What options with the yum command would you use to remove a package?
You can use the remove or erase options with yum to remove a package.
VNC is used to control a remote desktop session.
mkfs.ext4
The NFS service uses TCP port 2049 by default.

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

31. Is it possible to share files among groups - What permissions would you set on the directory to accomplish file sharing if possible?
LUKS encryption
By default - the rndc utility listens on port 953.
By combining a TFTP server - PXE boot - and DHCP server - you can fully automate the kickstart installation process.
Use the setgid flag to create the appropriate permissions (chmod 2770).

32. The INPUT chain being used is the default under Red Hat Enterprise Linux 5. This rule...
The -t nfs option is used with the mount command to mount NFS resources.
generates errors under Red Hat Enterprise Linux 6
getsebool
run on any port you'd like (provided that port is available)

33. Runlevel 0 ___________. Runlevel 6 reboots the system.
Use the top command to view CPU and memory usage.
kickstart installations to work
The /etc/exports file needs to contain any directory that you want to export - including which options you'd like to use as well.
halts the system

34. What option needs to be used with the mount command to mount an NFS resource?
A virtual host is a way of hosting multiple sites using a single IP address.
The -t nfs option is used with the mount command to mount NFS resources.
atq
SSH is used for secure remote management of Linux systems.

35. What are the two config files for Postfix called?
Sendmail
The two main config files are master.cf and main.cf.
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.
defining a %pre section although it is rarely used

36. A service needs to have _______________ to be able to use it.
chkconfig sshd off
SSH is used for secure remote management of Linux systems.
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.
support for TCP Wrappers

37. What is the rndc utility used for?
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
The rndc utility provides a method for managing the DNS server remotely and securely.
The three utilities are: route - ping - and nslookup.
The SMTP service runs on TCP port 110.

38. What benefit does a web proxy provide to your network?
SELinux Booleans provide restrictions to different aspects of a service.
A web proxy can provide multiple benefits - including security - web page caching for faster load times - and load balancing.
The tcpdump command is used to monitor network connections on different interfaces.
defining a %pre section although it is rarely used

39. To grow a file system
Use the resize2fs command to grow a file system.
Use the top command to view CPU and memory usage.
Typing the mail or mutt command allows you to read mail from the command line.
Upstart. The Upstart utility is now used in the boot process for Red Hat Enterprise Linux 6.

40. The default SMTP service has been changed from _________ to Postfix in Red Hat Enterprise Linux 6.
Sendmail
Enforcing during installation
The testparm command allows you to check for syntax errors in the /etc/samba/smb.conf file.
Using the chcon command - you can change the context of a file to work with Apache.

41. 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.
By using centralized authentication - you don't need to re-create or maintain multiple accounts across every system in your organization.
The NFS service uses TCP port 2049 by default.
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.
Enforcing during installation

42. What is the xinetd service used for?
The file system where ACLs will be implemented must be mounted with the acl option before ACLs will work properly.
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 xinetd daemon is used to control and/or run multiple system services. One example is a TFTP server.
lvdisplay

43. How would you disable SELinux protection for NFS - allowing shares to be read/write?
setsebool -P nfs_export_all_rw=1
useradd -c "Jr Admin" George
The five directories are BUILD - RPMS - SOURCES - SPECS - and SRPMS.
Use the /usr/share/doc/dovecot-1.0.7/examples/mkcert.sh command after editing the /etc/pki/dovecot/dovecot-openssl.cnf file.

44. What command can you use to view NFS statistics?
The smbpasswd command is used to create Samba users.
The nfsstat command can be used to view NFS statistics.
The TFTP server uses UDP port 69.
The -t nfs option is used with the mount command to mount NFS resources.

45. What command can you use to test the config files before starting the DNS service?
service named configtest
The TFTP server uses UDP port 69.
The rndc utility provides a method for managing the DNS server remotely and securely.
For Apache to run a secure site - the mod_ssl package is required to be installed.

46. What is the top command used for?
chcon
service sshd statuts
Use the yum groupinstall command to install multiple packages in a single group at once.
Use the top command to view CPU and memory usage.

47. What is the name of the package used to install an FTP?
The format of the /etc/shadow file is <username>:<encrypted password>:<last passwd change>:<min>:<max>:<warn>:<inactive>:<expires>:<not used>.
chkconfig xinetd --list
The vsftpd package is used to install an FTP server.
rpcbind service

48. What command is used to change the mail server from Sendmail to Postfix (useful only if you have both installed)?
The /var/liv/dhcpd/dhcpd.leases file contains all clients IP address currently in use.
choose which mode you'd like it to operate in
Sendmail
alternatives --config mta

49. What does ifconfig 172.168.1.100 netmask 255.255.255.0 eth1 do?
A virtual host is a way of hosting multiple sites using a single IP address.
setsebool -P nfs_export_all_rw=1
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.
getfacl

50. GRUB has three stages. Can you name them?
The htpasswd command can be used to password-protect a web page.
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
Physical volumes - volume groups - and logical volumes.
The du and df commands are used to view available space on the system.