Deck 14: Troubleshooting, Performance, and Security

Question 1

The shell restricts the number of file handles that programs can open to ____ by default.

A) 256
B) 512
C) 1024
D) 2048

Answer 1

C

Question 2

Performance problems are caused by hardware, not software.

Answer 2

False

Question 3

The free command can be used to display the total amounts of physical and swap memory in Kilobytes and their utilizations. _________________________

Answer 3

True

Question 4

When applications run into difficulties gaining resources during execution and stop functioning, restarting the process using a(n) ____ often solves this problem.

A) SIGINT
B) SIGQUIT
C) SIGTERM
D) SIGHUP

Question 5

A room where you lock important computers, such as Linux servers, and to which only Linux administrators or trusted users have key access is commonly called a(n) server closet. _________________________

Question 6

Running background processes using the ____ command allows you to exit your command-line shell without ending any background processes.

A) continue
B) noshell
C) nokill
D) nohup

Question 7

By default, sar commands are scheduled using the cron daemon to run every ____ minutes in Fedora 13.

A) two
B) five
C) ten
D) thirty

Question 8

Almost all hardware problems are the result of damaged hardware.

Question 9

The ____ option for the sar command is used to display swap statistics.

A) -B
B) -b
C) -s
D) -q

Question 10

The ____ option for the sar command is used to displays statistics for the processor queue.

A) -r
B) -c
C) -q
D) -v

Question 11

To identify any missing files in a package or package dependency, you can use the ____ option to the rpm command, followed by the name of the package.

A) -v
B) -m
C) -V
D) -M

Question 12

All Linux problems can be divided into ____ categories.

A) two
B) three
C) four
D) five

Question 13

If the / filesystem becomes corrupted, the system is unstable and must be turned off.

Question 14

Performing regular system backups and identifying potential problem areas are examples of reactive maintenance.

Question 15

The mpstat utility measures the flow of information to and from disk devices. _________________________

Question 16

The ____ command can be used to obtain root access when you need to perform an administrative task.

A) swu
B) sudo
C) su
D) switchu

Question 17

To identify which shared libraries are required by a certain program, you can use the ldconfig command. _________________________

Question 18

For the GRUB boot loader, errors are typically the result of a missing file in the /boot directory. _________________________

Question 19

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.

Question 20

____ are the most common hardware component to fail on Linux systems.

A) Floppy drives
B) Hard disks
C) NICs
D) Video cards

Question 21

When performance issues arise, you can compare the output of performance utilities to the ____________________ values found in the system log book.

Question 22

Viewing the output of the ____________________ command or the contents of the /var/log/boot.log and /var/log/messages log files can isolate most hardware problems.

Question 23

To see what network services are running on your network, you can run the ____ command.

A) nmap
B) map
C) networkmap
D) nm

Question 24

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
The file that contains a list of directories that contain shared libraries.

Question 25

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
A utility that can be used to indicate whether more physical memory is required.

Question 26

Asymmetric encryption uses a pair of keys that are uniquely generated on each system: a(n) ____ key and a(n) ____ key.

A) authentication ; encryption
B) public ; private
C) unidirectional ; bidirectional
D) data ; code

Question 27

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
The measures taken to reduce future system problems.

Question 28

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
A tool used by network applications that authenticate users.

Question 29

In SSH, the /etc/ssh directory stores the DSA public key in the ____ file.

A) ssh_host_dsa_key
B) ssh_host_dsa_key. pub
C) ssh_target_dsa_key
D) ssh_target_dsa_key.pub

Question 30

A(n) ____ is a program that can start a network daemon.

A) network bootstrapper
B) TCP wrapper
C) IP wrapper
D) daemon launcher

Question 31

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
A command that can be used to increase the number of processes that users can start in the shell.

Question 32

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
A command that gives users the ability to run certain commands as the root user.

Question 33

Some peripheral devices can perform a great deal of processing that is normally performed by the CPU; this is known as ____________________.

Question 34

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
The directory that contains most system log files.

Question 35

The ____ option to the iptables command can be used to specify the destination address of packets for a rule.

A) -D
B) -L
C) -F
D) -d

Question 36

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
Open source program for Braille translation

Question 37

Match each term with the correct statement below.
a.proactive maintenance
b.ulimit
c./etc/ld.so.conf
d.vmstat
e./var/log
f.sudo
g.Orca
h.reactive maintenance
i.Pluggable Authentication Modules (PAM)
The measures taken when system problems arise.

Question 38

Processes can initiate numerous connections, called ____________________, to files on the filesystem in addition to standard input, standard output, and standard error.

Question 39

The ____ option to the iptables command can be used to specify the default policy for a certain chain type.

A) -P
B) -C
C) -p
D) -c

Question 40

The ____________________ command is used to view the current SELinux status.

Question 41

How can netfilter/iptables be used to create a firewall service?

Question 42

How is the mpstat utility used? What information does it provide, and how can that information be interpreted?

Question 43

What are the two golden rules that should guide you during any troubleshooting process? Describe each rule.

Question 44

How can you identify filesystem corruption? How should you troubleshoot filesystem corruption on a non-critical partition?

Question 45

What methods can be used to physically secure local computers?