Advance Server Lesson 6 Quiz
Select the option that, when used with the sar command, displays swap statistics:
-B
What option for the iptables command can be used to specify the default policy for a certain chain type?
-P
What option can be specified with the rpm command to identify any missing files in a package or package dependency?
-V
Select the iptables option that specifies the destination address of packets for a rule:
-d
On a system that is not using Systemd, what two log files contain information related to PAM?
/var/log/secure /var/log/auth.log
1. The connections that a program makes to files on a filesystem. 2. A measure of normal system activity. 3. The process of embedding network packets within other network packets. 4. A command that lists the files that are currently being viewed or modified by software programs and users. 5. A program that can be used to detect unauthorized access to a Linux system. 6. A software program that can be used to automatically authenticate users using their private key. 7. A common IDS for Linux that monitors files and directories. 8. An attack in which a network service is altered in memory 9. A command that can be used to scan ports on network computers. 10. A daemon used on some Linux systems to provide for easier configuration of netfilter via the ipchains command.
1. file handles 2. baseline 3. tunneling 4. lsof command 5. Intrusion Detection System (IDS) 6. SSH agent 7. tripwire 8. buffer overrun 9. nmap command 10. firewall daemon (firewalld)
By default, the shell on a Linux system limits the number of filehandles a program can have open to what value?
1024
Almost all hardware problems are the result of damaged hardware.
False
If some users, such as software developers, need to run certain commands as the root user in certain situations, it is best to allow them to log on to the root user account via the su command.
False
Performance problems are caused by hardware, not software.
False
Performing regular system backups and identifying potential problem areas are examples of reactive maintenance.
False
What is the most common hardware component to fail on a Linux system?
Hard disks
Older hardware that is malfunctioning may begin to send large amounts of information to the CPU when not in use. What is this process called?
Jabbering
Asymmetric encryption uses a pair of keys that are unique generated on each system. What are these two keys called?
Private Key Public Key
If applications run into difficulties gaining resources during execution and stop functioning, restarting the process using a specific kill signal may resolve the issue. Select the proper kill signal below:
SIGHUP
What are the two most common technologies that provide asymmetric encryption on Linux systems?
Secure Shell (SSH) GNU Privacy Guard (GPG)
If network services that are started by inetd or xinetd are in use, what can be used to provide extra security?
TCP wrapper
If the / filesystem becomes corrupted, the system is unstable and must be turned off.
True
How often are sar commands scheduled to run on both Fedora 20 and Ubuntu Server 14.04?
every ten minutes
What two commands below can display memory information and swap usage?
free vmstat
What command can be used to view what shared libraries are required by a certain program?
ldd
Running background processes using what command allows you to exit your command-line shell without ending any background processes?
nohup
What file contains the DSA public key in the /etc/ssh directory?
ssh_host_dsa_key. pub
What command can be used to change the maximum number of file handles that can be used by a program?
ulimit
What two iptables options are used to specify the source and destination ports for a rule?
-dport -sport
After downloading an installing any shared libraries, what should be done to ensure the list of shared library directories and the list of shared libraries are updated?
Run the ldconfig command.
Assistive technologies are configured using what utility on Fedora 20 in GNOME?
Universal Access
If X Windows fails to start, what command can be used to troubleshoot the issue?
xwininfo