CSF2903
Operating Systems & Security
Lab 12 – Configuring FTP
Summary:
This lab gives you an opportunity to configure/test basic FTP service with firewall
protection.
I.
Configure FTP service
1. Log in to your lab PC and start up Kali Server Virtual Machine.
2. Log in to the VM with your user (password “Nettwerk1”). Open a
terminal & switch to the root account (password “Letmein1”.)
3. Check on the status of the vsftpd service. What command did you use?
4. Configuration files for vsftpd are in the /etc chown --helpdirectory. Which
file controls the FTP daemon?
5. service vsftpd stop
6. An account called FTP will be added automatically to your server, so lets
create an appropriate directory for the anonymous user:
mkdir -p /var/ftp/pub
7. Give the appropriate permissions:
chown -hR ftp:ftp /var/ftp
chmod 555 /var/ftp/pub
8. Back-up the original vstfpd.conf file with:
cp /etc/vsftpd.conf /etc/vsftp_conf_original
9. Open the main configuration file. Some of the uncommented directives
are listed in the following table. Add a short description beside each
directive.
Directive=Value
Description
listen=YES
anonymous_enable=YES
local_enable=YES
write_enable=YES
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CSF2903
Operating Systems & Security
local_umask=022
dirmessage_enable=YES
connect_from_port_20=YES
ftpd_banner=CSF2903 ServerX.
anon_root=/var/ftp/pub
10.Flush all firewall rules and save the Firewall.
11.Start up the FTP service. What command did you use?
12.Create a file called ftptest.txt in the /var/ftp/pub directory. Put the
following text in the file: “Hello FTP user!”
II.
Test FTP service
13.Open a terminal. Start an FTP session and connect to your server VM.
(Hint – use the ftp command). Write down the exact command you used.
14.Login to the FTP server as “ftp” with no password. What is your current
directory on the FTP server?
15.Download the file ftptest.txt. What command did you use? (Hint – check
the slide titled “Transferring Files”)
16.Open another terminal. Confirm that the file was transferred properly.
17.In the first terminal, close the FTP connection to the server (hint – check
the slide titled “Open & Close a Session”).
III.
Iptables protection
18.Insert iptables rules to accept connections from any machine on the
server’s subnet to the FTP data and control ports (20 and 21). Save your
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CSF2903
Operating Systems & Security
iptables changes. Write down the rule to allow TCP connections on these
ports.
19.Open a new FTP connection to the server. Login to the FTP server as “ftp”
with no password. (If you have done the iptables rules properly, this will
now work.)
20.Terminate the FTP session.
Ις.
User FTP Configuration
21.Create a user: Create a user to test ftp interaction called ftp1 with the
password Nettwerk1
22.In your user account create a file called fr_user.txt in the home directory
with the text “This is from the student user account”.
23.Log into the FTP1 account and create the fr_ftp1.txt in the home
directory with the text “ This is from the ftp1 user account”.
24.Open a terminal and create a connection to the ftp server of the localhost
and log into the ftp1 account with the password Nettwerk1:
25.Download the file fr_ftp1.txt. What command did you use?
26.Upload the file fr_user.txt. What command did you use?
27.What files are in ftp1 home directory. What command did you use? Verify
by opening another terminal and logging into ftp1 account.
28.End of Lab: Suspend or shut down both VMs. Log out. Have a nice day

Lab 12 – FTP
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Linux Command Reference
[page 1 of 2]
Commands
Description
users
Displays currently logged in users (no details, only usernames)
w
Displays currently logged in users with some details
who
Displays currently logged in users with some details
id user-name
Displays user-id, and group-id of any user
whoami
Displays username of currently logged on user
su user-name
Switch to another user
sudo command
Run a command with elevated privilege
history
Displays history of all commands used in bash session
man command
Display the help of given command from manual pages
command - - help
Display the brief help of given command
clear
Clear the screen in bash shell
chmod 777 file-name
Change file or dir permissions. 777 means a 3 digit octal number, e.g. 640
chown user:group file-name
Change file/directory ownership
umask
Display/change default permissions
fdisk hard-disk-name
To create/delete a partition. Disk name can be /dev/sda or /dev/sdb etc.
mkfs -t fs-type
Format a hard disk partition. fs-type is file system, i.e., ext4 or ntfs etc.
partition-name
mount partition-name mount-point
Mount a formatted partition to a specified empty directory (mount point)
umount partition-name
Un-mount a formatted partition
df
Display free space on mounted partitions
useradd username [options]
Create user account. Option can be -c -g -G -u etc.
passwd username
Create or modify a user password
usermod username [options]
Modify user account properties. Options can be -c -g -G -u etc.
userdel username [options]
Delete a user account. Option can be -r etc.
groupadd groupname [options]
Create a group account Option can be -g etc.
groupdel groupname
Delete a group account
groupmod groupname [options]
Modify group properties Option can be -g etc.
ifconfig
Display, or modify a network interface details
ifconfig int-name ip-address
netmask subnet-mask
Set the IP address of a network interface card. int-name is the network
interface name, such as eth0 or enp0s3 etc.
ping ip-address [options]
Check network connection to another host. Options can be -c -i -s etc.
traceroute ip-address
Display path to another host
netstat [options]
Display network connections & statistics. Options can be -u -t -p -l etc.
rpm -q package
Check whether given package is installed in the operating system or not.
yum option package
Software package manager to install, remove, or update a package.
service service-name option
To start, stop, restart, or check the status of a service.
chkconfig service-name
To check if a service is enabled to auto-start at boot time
chkconfig service-name option
Option can be on to enable, or off to disable a service at boot time
Linux Command Reference
[page 2 of 2]
Commands
Description
ls [dir-name] [options]
Display list of files and directory. Option can be -l –a etc.
cd dir-name
Change the current directory (going into a directory/folder)
cd ..
Change the current directory to the parent directory
pwd
Display current working directory
mkdir dir-name
Create a directory or multiple directories, e.g., mkdir dir1 dir2 dir3 etc.
rmdir dir-name
Delete a directory or multiple directories
touch file-name
Create an empty file or multiple empty files, e.g., touch file1 file2 file3 etc.
vi file-name
vi text editor to open an existing file to edit, or create a new file.
gedit file-name
gedit text editor to open an existing file to edit, or create a new file.
cp source destination
Copy a file, or directory from one location to another.
rm [options] file-dir-name
Delete a file (or directory with -r). Options can be -r -I -v etc.
mv source destination
To move from one location to another, or to rename a file.
cat file-name
Display all contents of a file.
more file-name
Display all contents of a file, but one screen at a time.
less file-name
Display all contents of a file, but one screen at a time with scrolling facility.
head [-n lines] file-name
If number of lines not specified it will display first 10 lines of a text file
tail [-n lines] file-name
If number of lines not specified it will display last 10 lines of a text file
find
Finds files and directories on the file system
locate file-name
Finds files and directories on the file system
grep string file-name
Search a string in given file
/etc/vsftpd/vsftpd.conf
FTP Server configuration file with complete location
/var/ftp
Default location of FTP site to download or upload files
vsftpd
Background service name for FTP Server
ftp ip-address
Command line FTP client utility to connect to FTP server
/etc/hosts
Local host file to resolve DNS names
/etc/ssh/ssh_config
System-wide SSH configuration file
sshd
Background service name for SSH Server
ssh user@ip-address
Command line SSH client utility to connect to remote SSH Server
scp source destination
Command line SSH client utility to transfer files to and from SSH Server
/etc/hosts.allow
Host access file used by TCP Wrappers to allow access for services
/etc/hosts.deny
Host access file used by TCP Wrappers to deny access for services
iptables
Command line firewall utility to manage the firewall in Linux
iptables [options]
Options may have chain name (INPUT/OUTPUT/FORWARD), -A -D -L etc.
[]
options
square bracket means optional, you may use the command without this parameter.
It means the features of command (sometime also referred as switches), such as –a option is used in
the ls command as ls -a to show all files (including hidden files).
Unix/Linux Command Reference
File Commands
.com
System Info
ls – directory listing
date – show the current date and time
ls -al – formatted listing with hidden files
cal – show this month's calendar
cd dir - change directory to dir
uptime – show current uptime
cd – change to home
w – display who is online
pwd – show current directory
whoami – who you are logged in as
mkdir dir – create a directory dir
finger user – display information about user
rm file – delete file
uname -a – show kernel information
rm -r dir – delete directory dir
cat /proc/cpuinfo – cpu information
rm -f file – force remove file
cat /proc/meminfo – memory information
rm -rf dir – force remove directory dir *
man command – show the manual for command
cp file1 file2 – copy file1 to file2
df – show disk usage
cp -r dir1 dir2 – copy dir1 to dir2; create dir2 if it du – show directory space usage
doesn't exist
free – show memory and swap usage
mv file1 file2 – rename or move file1 to file2
whereis app – show possible locations of app
if file2 is an existing directory, moves file1 into
which app – show which app will be run by default
directory file2
Compression
ln -s file link – create symbolic link link to file
tar cf file.tar files – create a tar named
touch file – create or update file
file.tar containing files
cat > file – places standard input into file
tar xf file.tar – extract the files from file.tar
more file – output the contents of file
tar czf file.tar.gz files – create a tar with
head file – output the first 10 lines of file
Gzip compression
tail file – output the last 10 lines of file
tar xzf file.tar.gz – extract a tar using Gzip
tail -f file – output the contents of file as it
tar cjf file.tar.bz2 – create a tar with Bzip2
grows, starting with the last 10 lines
compression
Process Management
tar xjf file.tar.bz2 – extract a tar using Bzip2
ps – display your currently active processes
gzip file – compresses file and renames it to
top – display all running processes
file.gz
kill pid – kill process id pid
gzip -d file.gz – decompresses file.gz back to
killall proc – kill all processes named proc *
file
bg – lists stopped or background jobs; resume a
stopped job in the background
Network
fg – brings the most recent job to foreground
ping host – ping host and output results
fg n – brings job n to the foreground
whois domain – get whois information for domain
dig domain – get DNS information for domain
File Permissions
dig -x host – reverse lookup host
chmod octal file – change the permissions of file
wget file – download file
to octal, which can be found separately for user,
wget -c file – continue a stopped download
group, and world by adding:
● 4 – read (r)
Installation
● 2 – write (w)
Install from source:
● 1 – execute (x)
./configure
Examples:
make
chmod 777 – read, write, execute for all
make install
chmod 755 – rwx for owner, rx for group and world
dpkg -i pkg.deb – install a package (Debian)
For more options, see man chmod.
rpm -Uvh pkg.rpm – install a package (RPM)
SSH
ssh user@host – connect to host as user
ssh -p port user@host – connect to host on port
port as user
ssh-copy-id user@host – add your key to host for
user to enable a keyed or passwordless login
Searching
Shortcuts
Ctrl+C – halts the current command
Ctrl+Z – stops the current command, resume with
fg in the foreground or bg in the background
Ctrl+D – log out of current session, similar to exit
Ctrl+W – erases one word in the current line
Ctrl+U – erases the whole line
Ctrl+R – type to bring up a recent command
!! - repeats the last command
exit – log out of current session
grep pattern files – search for pattern in files
grep -r pattern dir – search recursively for
pattern in dir
command | grep pattern – search for pattern in the
output of command
* use with extreme caution.
locate file – find all instances of file
Managing Hard Disks
and Partitions
Practice Lab
CSF 2903
OPERATING SYSTEMS ADMINISTRATION AND SECURITY
Managing Disks & Partitions (Practice Lab)
Table of Contents
Hard disk and Partitions Naming in Linux ............................................................................................................................... 2
Managing Disks and Partitions ................................................................................................................................................ 2
Display List of disks and Partitions in Linux............................................................................................................................. 2
Display list of partition on a selected disk .............................................................................................................................. 1
Checking the list of mounted Partitions and free space ......................................................................................................... 1
Create a partition of size 4 GB on 2nd hard disk in your computer. ...................................................................................... 2
Format the partition with ext4 file system ............................................................................................................................. 3
Mount the partition ................................................................................................................................................................ 4
The command to confirm that the partition is mounted. ...................................................................................................... 4
The command to un-mount the partition............................................................................................................................... 5
How to delete a partition (only delete if it is asked in exam or lab)....................................................................................... 5
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Hard disk and Partitions Naming in Linux
In Linux operating system, all device files are saved in /dev sub-directory. The Hard disk is represented as “sd”,
and the first hard disk is represented with letter “a”, second hard drive is represented with letter “b” etc.
Therefore the file /dev/sda will represent the 1st Hard disk in Linux operating system.
/dev/sdb = 2nd Hard Disk
/dev/sdb3 = 3 partition on 2nd Hard Disk
/dev/sde = 5th Hard Disk
/dev/sde1 = 1st Partition on 5th Hard Disk
Managing Disks and Partitions
To manage Disks and Partitions in Linux operating system, you have to be administrator, i.e., user “root”.
Instead of su root you can also type only su
In lab computers, the password for user “root” is csf2903
Display List of disks and Partitions in Linux
fdisk –l
to list of all partitions & drive on Linux computer
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Display list of partition on a selected disk
fdisk –l /dev/sdb
to see all partition only on hard disk 2
Checking the list of mounted Partitions and free space
df
to check the free space on mounted disk
See the 1st partition on 1st hard disk, which is /dev/sda1 is mounted (loaded) in an empty directory name boot
in / this is a partition made while we install linux to boot the computer
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Create a partition of size 4 GB on 2nd hard disk in your computer.
# fdisk /dev/sdb
command to manage the hard disk number 2 in Linux
n
type n to create a new partition, and press ENTER key
3 times, press ENTER key
 1st enter
 2nd enter
 3rd enter
Give size as +4G
p
w
primary partition is selected by default
1st primary partition is selected by default
2048 is selected by default for first sector
write the partition size starting with + and ending with G and press ENTER key
type p to print the partition table, and press ENTER key
type w to write (save) the partition table and exit
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Format the partition with ext4 file system
mkfs -t ext4 /dev/sdb1
command to format the 1st partition on hard disk number 2
You can also format as ntfs or vfat (windows file system) using following commands
mkfs -t ntfs /dev/sdb1
mkfs -t vfat /dev/sdb1
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Mount the partition
In Linux you cannot access any drive with drive letter. You must have an empty folder that you can link with
partitions in Linux using mount command. Mount means loading the partition in a mount point (empty
folder/directory)
If you don’t have any empty directory, then create an empty folder (just once), you do not need to create it
every time.
mkdir saeed
(only create if you don’t have)
mount /dev/sdb1 saeed
if you are in same location where you created the directory
mount /dev/sdb1 /home/hctuser/saaed
otherwise type full path for the directory saeed
The command to confirm that the partition is mounted.
df
df –h
(display the size in human readable format, i.e., KB, GB (Giga Byte)
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Managing Disks & Partitions (Practice Lab)
The command to un-mount the partition.
umount /dev/sdb1
How to delete a partition
Deleting a partition will erase all your data. You have to use fdisk program to delete the partition.
Press “w” if you wish to save and exit, otherwise press “q” to quit the fdisk program without saving.
CSF 2903: OS Administration & Security
Page 5
Managing Hard Disks
and Partitions
Practice Lab
CSF 2903
OPERATING SYSTEMS ADMINISTRATION AND SECURITY
Managing Disks & Partitions (Practice Lab)
Table of Contents
Hard disk and Partitions Naming in Linux ............................................................................................................................... 2
Managing Disks and Partitions ................................................................................................................................................ 2
Display List of disks and Partitions in Linux............................................................................................................................. 2
Display list of partition on a selected disk .............................................................................................................................. 1
Checking the list of mounted Partitions and free space ......................................................................................................... 1
Create a partition of size 4 GB on 2nd hard disk in your computer. ...................................................................................... 2
Format the partition with ext4 file system ............................................................................................................................. 3
Mount the partition ................................................................................................................................................................ 4
The command to confirm that the partition is mounted. ...................................................................................................... 4
The command to un-mount the partition............................................................................................................................... 5
How to delete a partition (only delete if it is asked in exam or lab)....................................................................................... 5
CSF 2903: OS Administration & Security
Page 1
Managing Disks & Partitions (Practice Lab)
Hard disk and Partitions Naming in Linux
In Linux operating system, all device files are saved in /dev sub-directory. The Hard disk is represented as “sd”,
and the first hard disk is represented with letter “a”, second hard drive is represented with letter “b” etc.
Therefore the file /dev/sda will represent the 1st Hard disk in Linux operating system.
/dev/sdb = 2nd Hard Disk
/dev/sdb3 = 3 partition on 2nd Hard Disk
/dev/sde = 5th Hard Disk
/dev/sde1 = 1st Partition on 5th Hard Disk
Managing Disks and Partitions
To manage Disks and Partitions in Linux operating system, you have to be administrator, i.e., user “root”.
Instead of su root you can also type only su
In lab computers, the password for user “root” is csf2903
Display List of disks and Partitions in Linux
fdisk –l
to list of all partitions & drive on Linux computer
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Display list of partition on a selected disk
fdisk –l /dev/sdb
to see all partition only on hard disk 2
Checking the list of mounted Partitions and free space
df
to check the free space on mounted disk
See the 1st partition on 1st hard disk, which is /dev/sda1 is mounted (loaded) in an empty directory name boot
in / this is a partition made while we install linux to boot the computer
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Create a partition of size 4 GB on 2nd hard disk in your computer.
# fdisk /dev/sdb
command to manage the hard disk number 2 in Linux
n
type n to create a new partition, and press ENTER key
3 times, press ENTER key
 1st enter
 2nd enter
 3rd enter
Give size as +4G
p
w
primary partition is selected by default
1st primary partition is selected by default
2048 is selected by default for first sector
write the partition size starting with + and ending with G and press ENTER key
type p to print the partition table, and press ENTER key
type w to write (save) the partition table and exit
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Format the partition with ext4 file system
mkfs -t ext4 /dev/sdb1
command to format the 1st partition on hard disk number 2
You can also format as ntfs or vfat (windows file system) using following commands
mkfs -t ntfs /dev/sdb1
mkfs -t vfat /dev/sdb1
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
Mount the partition
In Linux you cannot access any drive with drive letter. You must have an empty folder that you can link with
partitions in Linux using mount command. Mount means loading the partition in a mount point (empty
folder/directory)
If you don’t have any empty directory, then create an empty folder (just once), you do not need to create it
every time.
mkdir saeed
(only create if you don’t have)
mount /dev/sdb1 saeed
if you are in same location where you created the directory
mount /dev/sdb1 /home/hctuser/saaed
otherwise type full path for the directory saeed
The command to confirm that the partition is mounted.
df
df –h
(display the size in human readable format, i.e., KB, GB (Giga Byte)
CSF 2903: OS Administration & Security
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Managing Disks & Partitions (Practice Lab)
The command to un-mount the partition.
umount /dev/sdb1
How to delete a partition
Deleting a partition will erase all your data. You have to use fdisk program to delete the partition.
Press “w” if you wish to save and exit, otherwise press “q” to quit the fdisk program without saving.
CSF 2903: OS Administration & Security
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