Pregunta 1
Pregunta
What kind of hardware is represented by the device name /dev/hda?
Respuesta
-
IDE Hard Drive
-
SCSI Hard Drive
-
SATA Hard Drive
-
Sound Card
Pregunta 2
Pregunta
What file should you query to determine whether there is an IRQ conflict on your system?
Respuesta
-
/proc/interrupts
-
/proc/cpuinfo
-
/proc/meminfo
-
/proc/irqstatus
Pregunta 3
Pregunta
Which of the following are arguments you can pass to the kernel at boot time
to tell it to start in runlevel 1 (single-user mode)? (Select two)
Pregunta 4
Pregunta
Which process is referred to as the “mother of all processes” and always has PID 1?
Respuesta
-
init
-
mother
-
admin
-
administrator
Pregunta 5
Pregunta
What is the command to delete the default gateway from the system IP routing table?
(Choose TWO correct answers.)
Respuesta
-
oute del default
-
fconfig unset default
-
netstat -r default
-
ip route del default
-
sysctl ipv4.default_gw=0
Pregunta 6
Pregunta
What is true regarding a default route?
Respuesta
-
The default route is always used first. When the default route is not available more specific routes are tried.
-
When a default route is set, all other routes are disabled until the default route is deleted.
-
The default route is only used if there is not a more specific route to a destination host or network.
-
Without a default route, no network communication even in directly attached networks is possible.
Pregunta 7
Pregunta
What is true regarding TCP port 23?
Respuesta
-
Port 23 is the well known port for the telnet service which is a plain text protocol that should no longer be used.
-
Port 23 is the well known port for the SSH service which provides secure logins.
-
Port 23 is the well known port for the rlogin service which is SSL secured by default.
-
Port 23 is the well known port for the system login services which are encrypted when the user runs the starttls command in his login shell.
Pregunta 8
Pregunta
Which of the following IPv4 networks are reserved by IANA for private address assignment
and private routing? (Choose THREE correct answers.)
Respuesta
-
127.0.0.0/8
-
10.0.0.0/8
-
169.255.0.0/16
-
172.16.0.0/12
-
192.168.0.0/16
Pregunta 9
Pregunta
Which of the following lines are valid in the file /etc/hosts? (Choose TWO correct answers.)
Respuesta
-
2001:db8::15 www.example.com www
-
www.example.com www 203.0.13.15
-
203.0.113.15 www.example.com www
-
www.example.com,www 203.0.13.15,2001:db8::15
-
003.0.113.15,2001:db8::15 www.example.com www
Pregunta 10
Pregunta
Which of the following keywords can be used in the file /etc/nsswitch.conf to specify a
source for host name lookups? (Choose TWO correct answers.)
Respuesta
-
resolv
-
dns
-
remote
-
files
-
hosts
Pregunta 11
Pregunta
Which of the following may occur as a consequence of using the command ifconfig?
(Choose THREE correct answers.)
Respuesta
-
New name servers may be added to the resolver configuration.
-
Network interfaces may become active or inactive.
-
The routing table may change.
-
IP addresses may change.
-
The system's host name may change.
Pregunta 12
Pregunta
What is the purpose of the nsswitch.conf file?
Respuesta
-
It is used to configure where the C library looks for system information such as host names and user passwords.
-
It is used to configure network protocol port numbers such as for HTTP or SMTP.
-
It is used to configure LDAP authentication services for the local system.
-
It is used to configure which network services will be turned on during the next system boot.
Pregunta 13
Pregunta
Which of the following commands preloads and manages keys that are used for automatic
authentication while logging in to other machines using SSH?
Respuesta
-
sshd
-
ssh-agent
-
ssh-keygen
-
ssh-add
Pregunta 14
Pregunta
When trying to unmount a device it is reported as being busy. Which of the following
commands could be used to determine which process is causing this?
Respuesta
-
debug
-
lsof
-
nessus
-
strace
-
traceroute
Pregunta 15
Pregunta
With X11 forwarding in ssh, what environment variable is automatically set in the remote host shell that is not set when X11 forwarding is not enabled? (Specify only the environment variable without any additional commands or values.)
[blank_start]DISPLAY, $DISPLAY[blank_end]
Pregunta 16
Pregunta
Which of the following programs uses the hosts.allow file to perform its main task of
checking for access control restrictions to system services?
Respuesta
-
tcpd
-
inetd
-
fingerd
-
mountd
-
xinetd
Pregunta 17
Pregunta
What is a purpose of an SSH host key?
Respuesta
-
It must be sent by any SSH client in addition to a user key in order to identify the client's host.
-
It provides the server's identity information to connecting SSH clients.
-
It is the root key by which all user SSH keys must be signed.
-
It authenticates any user that logs into a remote machine from the key's host.
-
It is used by system services like cron, syslog or a backup job to automatically connect to remote hosts.
Pregunta 18
Pregunta
Which of the following find commands will print out a list of files owned by root and with the
SUID bit set in /usr?
Respuesta
-
find /usr -uid 0 -perm +4000
-
find -user root +mode +s /usr
-
find -type suid -username root -d /usr
-
find /usr -ls \*s\* -u root
-
find /usr -suid -perm +4000
Pregunta 19
Pregunta
Which command is used to set restrictions on the size of a core file that is created for a
user when a program crashes?
Pregunta 20
Pregunta
Which configuration file would be edited to change default options for the OpenSSH
server?
Respuesta
-
/etc/ssh/sshd_config
-
/etc/ssh/ssh
-
/etc/ssh/server
-
/etc/ssh/ssh_config
-
/etc/ssh/ssh_server
Pregunta 21
Pregunta
Which of the following commands can be used to limit the amount of memory a user may
use?
Respuesta
-
umask
-
usermod
-
ulimit
-
passwd
-
chage
Pregunta 22
Pregunta
What environment variable holds the list of all directories that are searched by
the shell when you type a command name?
Respuesta
-
$LIST
-
$VIEW
-
$PATH
-
$ENV
-
None of the above
Pregunta 23
Pregunta
In the bash shell, entering the !! command has the same effect as which one of
the following (assuming bash is in emacs mode)?
Respuesta
-
Ctrl-P and Enter
-
Ctrl-N and Enter
-
Ctrl-U and Enter
-
!-2
-
!2
Pregunta 24
Pregunta
Name the command that displays pages from the online user’s manual and command reference.
[blank_start]man[blank_end]
Pregunta 25
Pregunta
Which of the following commands displays the comments from a bash script?
Select all that apply.
Respuesta
-
find “^#” /etc/rc.d/rc.local
-
sed ‘/^#/ !d’ /etc/init.d/httpd
-
grep ^# /etc/init.d/httpd
-
grep ^# /etc/passwd
-
locate “^#” /etc/skel/.bashrc
Pregunta 26
Pregunta
Which one of the following answers creates an environment variable VAR1,
present in the environment of a bash child process?
Respuesta
-
VAR1="fail" ; export VAR1
-
VAR1="fail" \ export VAR1
-
VAR1="fail"
-
set VAR1="fail" ; enable VAR1
-
export VAR1 \ VAR1="fail"
Pregunta 27
Pregunta
What SQL command is used to modify data present in a table?
Respuesta
-
INSERT
-
WHERE
-
UPDATE
-
OVERWRITE
-
JOIN
Pregunta 28
Pregunta
What output will the following command generate: seq -s";" -w 1 10
Pregunta 29
Pregunta
Adam wants to protect himself from inadvertently overwriting files when copy-
ing them, so he wants to alias cp to prevent overwrite. How should he go about
this? Select one.
Respuesta
-
Put alias cp='cp -i' in ~/.bashrc
-
Put alias cp='cp -i' in ~/.bash_profile
-
Put alias cp='cp -p' in ~/.bashrc
-
Put alias cp='cp -p' in ~/.bash_profile
-
Put alias cp = 'cp -I' in ~/.bashrc
Pregunta 30
Pregunta
Consider the following script, stored in a file with proper modes for execution:
#!/bin/bash
for $v1 in a1 a2
do
echo $v1
done
Which one of the following best represents the output produced on a terminal
by this script?
Respuesta
-
in
a1
a2
-
a1
a2
-
$v1
$v1
$v1
-
No output is produced, but the script executes correctly.
-
No output is produced, because the script has an error.
Pregunta 31
Pregunta
Monica consults the /etc/passwd file expecting to find encrypted passwords for
all of the users on her system. She sees the following:
jdoe:x:500:500::/home/jdoe:/bin/bash
bsmith:x:501:501::/home/bsmith:/bin/tcsh
Which of the following is true? Select one.
Respuesta
-
Accounts jdoe and bsmith have no passwords.
-
Accounts jdoe and bsmith are disabled.
-
The passwords are in /etc/passwd-.
-
The passwords are in /etc/shadow.
-
The passwords are in /etc/shadow-.
Pregunta 32
Pregunta
What is the main configuration file for X Windows?
Respuesta
-
/etc/xorg.conf
-
/etc/x11.conf
-
/etc/X11/x11.conf
-
/etc/X11/xorg.conf
-
None of the above
Pregunta 33
Pregunta
What file in the user’s home directory will an X Windows application look to
for configuration settings such as color and video mode?
Respuesta
-
~/.xinitrc
-
~/.xconfig
-
~/.Xresources
-
~/.xorg.conf
-
~/.bashrc
Pregunta 34
Pregunta
What is the protocol XDMCP used for?
Respuesta
-
Remote logging of X Windows events.
-
Remote control of a running X Windows display.
-
Graphical login support for the local host.
-
Graphical login support for remote hosts on the network.
-
None of the above.
Pregunta 35
Pregunta
Which of the following are not commonly used display managers for X Windows? Choose two.
Pregunta 36
Respuesta
-
A popular text editor for Linux.
-
A window manager.
-
An assistive technology that handles screen reading for a number of console
applications.
-
An assistive technology that provides a user with an on-screen keyboard.
-
None of the above.
Pregunta 37
Pregunta
Which one of the following outcomes results from the following command?
# chmod g+s /home/software
Respuesta
-
The SUID bit will be set for /home/software.
-
The SGID bit will be set for /home/software, preventing access by those not
a member of the software group.
-
The SGID bit will be set for /home/software, to keep group membership of
the directory consistent for all files created.
-
The sticky bit will be set for /home/software.
-
The sticky bit will be applied to all files in /home/software.
Pregunta 38
Pregunta
Which one of these files determines how messages are stored using syslogd?
Pregunta 39
Pregunta
Where are mail logs usually stored in a standard syslog setup?
Respuesta
-
/var/log/messages
-
/var/log/secure
-
/var/log/dmesg
-
/var/log/maillog
-
/var/maillog
Pregunta 40
Pregunta
How many hosts can exist on a subnet with mask 255.255.255.128? Select one.
Pregunta 41
Pregunta
For an Internet workstation with a single network interface, what routes must
be added to interface eth0 after it is initialized? Select one.
Respuesta
-
None
-
Interface
-
Interface and default gateway
-
Interface, local network, and default gateway
Pregunta 42
Pregunta
On a Linux server, what service is most likely “listening” on port 25? Select one.
Respuesta
-
Apache
-
SSHd
-
Postfix
-
Samba
-
v
Pregunta 43
Pregunta
Which one of these protocols is a Layer 4 connection-oriented protocol? Select one.
Pregunta 44
Pregunta
Which command will display information about Ethernet interface eth0? Select one.
Respuesta
-
cat /proc/eth/0
-
ifconfig eth0
-
ipconfig eth0
-
ipconfig /dev/eth0
-
cat /etc/eth0.conf
Pregunta 45
Pregunta
What does the printcap entry sd indicate? Select one.
Respuesta
-
The system default printer
-
A printer’s spool directory
-
A device file for the printer
-
A location where errors are stored
-
The printer driver
Pregunta 46
Pregunta
Which of the following is a valid entry in /etc/fstab for a remote NFS mount
from server fs1? Select one.
Respuesta
-
fs1:/proc /mnt/fs1 nfs defaults 9 9
-
/mnt/fs1 fs1:/proc nfs defaults 0 0
-
fs1:/home /mnt/fs1 nfs defaults 0 0
-
/mnt/fs1 fs1:/home nfs defaults 0 0
-
/home:fs1 /mnt/fs1 nfs defaults 0 0
Pregunta 47
Pregunta
Which network protocol is used by SSH and FTP? Select one.
Pregunta 48
Pregunta
Which of the following programs will display DNS information for a host?
Choose all that apply.
Respuesta
-
host
-
nslookup
-
nsstat
-
dig
-
ping
Pregunta 49
Pregunta
Which of the following statements regarding the ICMP protocol is not true?
Select one.
Pregunta 50
Pregunta
What server daemon resolves domain names to IP addresses for requesting hosts?
[blank_start]named[blank_end]
Pregunta 51
Pregunta
What function does a print filter serve? Select one.
Respuesta
-
It collates output from multiple users.
-
It translates various data formats into a page description language.
-
It rejects print requests from unauthorized users.
-
It rejects print requests from unauthorized hosts.
-
It analyzes print data and directs print requests to the appropriate lpd.
Pregunta 52
Pregunta
Consider the following excerpt from the file /etc/resolv.conf on a Linux workstation:
nameserver 127.0.0.1
nameserver 192.168.1.5
nameserver 192.168.250.2
What can be said about this configuration? Select one.
Respuesta
-
Two DNS servers on the public network are being used for resolution.
-
One DNS server on the local network is being used for resolution.
-
The configuration contains errors that will prevent the resolver from
functioning.
-
A caching-only nameserver is the first nameserver queried.
-
The resolver library will consult nameserver 192.168.250.2 first.
Pregunta 53
Pregunta
Name the file that contains simple mappings between IP addresses and system names.
[blank_start]/etc/hosts[blank_end]
Pregunta 54
Pregunta
What program can be used to interactively change the behavior of a print queue? Select one.
Pregunta 55
Pregunta
What program will display a list of each hop across the network to a specified destination? Select one.
Respuesta
-
tracert
-
rttrace
-
traceroute
-
routetrace
-
init
Pregunta 56
Pregunta
What is the system-wide bash configuration file called? Include the entire path.
[blank_start]/etc/profile[blank_end]
Pregunta 57
Pregunta
Consider the following line from /etc/passwd:
adamh:x:500:1000:Adam Haeder:/home/adamh:/bin/bash
What does the number 1000 mean?
Respuesta
-
User adamh has a UID of 1000.
-
The primary group that adamh belongs to is group 1000.
-
User adamh was the 1000th user created on this system
-
The password for adamh expires in 1000 days.
-
The secondary group that adamh belongs to is group 1000.
Pregunta 58
Pregunta
Consider the following trivial script called myscript:
#!/bin/bash
echo "Hello"
echo $myvar
Also consider this command sequence and result:
# set myvar='World'
# ./myscript
Hello
The script ran without error but didn’t echo World. Why not? Select one.
Respuesta
-
The syntax of the set command is incorrect.
-
The script executes in a new shell, and myvar wasn’t exported.
-
The #!/bin/bash syntax is incorrect.
-
The $myvar syntax is incorrect.
-
The script is sourced by the current shell, and myvar is available only to new
shells.
Pregunta 59
Pregunta
How does a process indicate to the controlling shell that it has exited with an error condition? Select one.
Respuesta
-
It prints an error message to stderr.
-
It prints an error message to stdout.
-
It sets an exit code with a zero value.
-
It sets an exit code with a nonzero value.
-
It causes a segmentation fault.
Pregunta 60
Pregunta
How can a nonprivileged user configure sendmail to forward mail to another account? Select one.
Respuesta
-
She can add a new entry in /etc/aliases.
-
She can create a .forward file containing the new address.
-
She can create an .alias file containing the new address.
-
She can create a sendmail.cf file containing the new address.
-
She cannot forward mail without assistance from the administrator.