Note: You may need to stop, start, or restart services associated with each

question $($sshd$,$ rsyslog, xinetd, ntpd$).$ You also need to install packages

$($telnet$-$server, telnet, nmap, xinetd$)$ using yum install pachage$\_$name.

Q$1.$ Issue a command to synchronize your server once with time.jccc$.$edu. Capture the

command you used and the output using Q$1.$

Q$2.$ Configure your server to synchronize $($persistently$)$ only with time.jccc$.$edu. Capture

your configuration using Q$2.$Verify your server is synchronized with time.jccc$.$edu using

Q$2$A$.$

Q$3.$ Configure lpr$.$info to send its log messages to $/$var$/$log$/$final$.$out. Capture your

configuration using Q$4.$

Q$4.$ Test your configuration using the logger utility with the content $$Testing lpr info$.$

Capture your testing command and the output of the file final.txt using Q$5.$ Verify the

existence of the file final.out using Q$4$A$.$

Q$5.$ Issue a command to display all files in your $/$ directory whose SUID and SGID $($both

are set$)$ are set. Capture the command and the output using Q$5.$

Q$6.$ Create a user called finals, use a utility or edit the appropriate file so that user finals

does not need a password to log into the GUI. Capture the method you used using Q$6.$

You need to show that you can login without using a password by logging out and

logging in as finals, Capture using Q$6$A$.$

Q$7.$ Create another user called johns, set johns password to be abc$123.$ Edit the sudoers

file so that johns can use the commands useradd and passwd without being a root user.

Capture your implementation using Q$7.$

Test your implementation by logging out and logging in as johns, without being a root,

use useradd and the passwd command to create a user called jony$1$ with password

abc$123.$ Capture the process using Q$7$A$.$

Q$8.$ Setup the maxlogins hard limit for user johns to $1.$ Login as johns, try to ssh to the

localhost using johns as the user id$.$ Capture the implementation using Q$8,$ and capture

the ssh attempt using Q$8$A$.$ You should not be able to complete the log in process. You

may need to make your implementation as comment after you finish this Question.

Q$9.$ Enable the server telnet on the xinetd configuration file or using individual file. You

may need to install packages $($xinetd$,$ telnet$-$server, telnet$)$ and restart services. Capture

your configuration using Q$9.$ Telnet to the dhcp ip address of your ens$160$ NIC. Login as

johns, capture the telnet session using Q$9$A$.$ A basic telnet file which need modification is

provided below.

Q$10.$ Configure TCP wrapper so that no one can connect to the sshd server using ssh$.$

Capture your implementation using Q$10.$ Test your implementation by trying to ssh to the

localhost as user$1.$ You should not be able to connect $($if you are already logged in as

user$1).$ Capture the ssh process using Q$10$A$.$ You may want to make your implementation

as a comment after you complete this question.

Q$11.$ Generate ssh public$/$private key pairs which can be used by the client johns. Capture

the command you used using Q$11.$ Display the name and locations of these keys using

Q$11$A$.$ Display the content of the private key using Q$11$B$.$ Attempt to ssh to the localhost

using the user johns. Capture the result using Q$11$C$.$

Q$12.$ Using gpg generate a key pair for the user jony$1,$ use $1024$ bits. List the key pairs

generated for user jony$1.$ Use the pass phrase abc$123.$ Capture the process using Q$12$

showing the key pair.

Q$13.$ Create a file called message with the content $$ Jony$1$ Final Exam Fall $2016.$

Encrypt this file using jony$1$ public key. Capture the encryption process using Q$13.$

Display the content of the encrypted file using Q$13$A$.$

service telnet

$\{$

disable $=$ no

flags $=$ REUSE

socket$\_$type $=$ stream

user $=$ root

wait $=$ no

server $=/$usr$/$sbin$/$in$.$telnetd

log$\_$on$\_$failure $+=$ USERID

$\}$