IT 441: Network Services Administration
Class #11 Exercise

Complete by: 4/4/2018

Log in to users.cs.umb.edu

• Log in to a Windows machine
  Enter your Unix username as the account name. Then enter your password.
• Run the ssh client
  Use the values in the table below to connect to users.
  
  

  ssh configuration parameter	value
  protocol	ssh
  ssh version	2
  ssh port	22
  host	users.cs.umb.edu
  user name	your unix username
  Authentication method	password

• Enter your password
  A dialog box will appear on the screen into which you must type the password for your Unix account.
• Make sure you are in your home directory
  

                  cd

• Go to your it441 directory

                  cd  it441

• Go to your ex directory
  

                  cd  ex

• Create an ex11 directory
  

                  mkdir  ex11

• Go to your ex11 directory
  

                  cd  ex11

• Execute the script command
  

                  script

• Use your perlsession alias to start the re.pl script.
  

                  perlsession

  (NOTE: If the perlsession alias is not recognized, or if re.pl cannot run, then double-check your Perl configuration, as well as your login shell vs. subshell environments!)

Hash operations

perl>  %ipMac = ('192.168.124.1', '2a:09:4e:3c:31:42', '192.168.124.2', '0e:88:4e:2a:56:07', '192.168.124.3', '1a:32:6f:5c:6b:1a');

perl>  print %ipMac;

perl>  print $ipMac{'192.168.124.1'};

perl>  print $ipMac{'192.168.124.2'};

perl>  print $ipMac{'192.168.124.3'};

perl>  $newIP = '192.168.124.4';

perl>  $ipMac{$newIP} = '2a:09:4e:2a:56:07';

perl>  print "IP $newIP has the MAC: $ipMac{$newIP}";

perl>  @ipMacKeys = keys(%ipMac);

perl>  foreach $k (@ipMacKeys) { print "$k\n" ;}

perl>  foreach $k (@ipMacKeys) { print "$k : $ipMac{$k}\n" ;}

perl>  @ipMacValues = values(%ipMac);

perl>  foreach $v (@ipMacValues) { print "$v\n" ;}

perl>  delete $ipMac{'192.168.124.2'};

perl>  @ipMacKeys = keys(%ipMac);

perl>  foreach $k (@ipMacKeys) { print "$k : $ipMac{$k}\n" ;}

perl>  $ipMac{'192.168.124.1'} = 'foo';

perl>  $ipMac{'192.168.124.4'} = 'bar';

perl>  foreach $k (@ipMacKeys) { print "$k : $ipMac{$k}\n" ; }

(Before closing your perlsession, experiment some with hashes to see what they will do...
In other words, make up some Perl code, similar to what you see above, but different enough to involve other aspects of hashes not covered here...
I will be looking for this.)

End the Perl Session

perl>  exit

End the script session

Use the exit command. You should then have a file called typescript in your current working directory.