Mismo Systems

1. Launch an EC2 Instance running on Ubuntu Server

1. Connect to Your EC2 Instance using endpoint connect or another way that is feasible to you 

1. Update Your Instance by the command (sudo apt update)

1. Install the updates by the command (sudo apt upgrade)

1. Install OpenSSH by the command  (sudo apt install -y openssh-server)
2. Configure SFTP:
     Create SFTP Group and User:

• sudo groupadd sftpusers

• sudo adduser sftp-user1
• sudo adduser sftp-user2
• sudo adduser normal-user

• Enter new UNIX password: 
• Retype new UNIX password: 

Add users into the groups
 sudo usermod -a -G sftpusers sftp-user1

sudo usermod -a -G sftpusers sftp-user1

            Create a directory for Restricted access

mkdir -p /var/www/public_ftp

            Set the owner of /var/www to root:

sudo chown root:root /var/www

Give root write permissions to the same directory, and give other      users only read and execute rights:

sudo chmod 755 /var/www

Now change the ownership of public_ftp directory that you have just created.

sudo chown sftp-user1:sftpsusers /var/www/public_ftp/

$ ls -lrt

total 0

Now, (testing not done for user-admin)

Create a user : sftp-admin
 

And give it permission to modify whole directory::  public_ftp

Create a subdirectory for each user inside the public_ftp directory and set permissions:

Give only User-sftp-vk-1 to add , modify and delete subfolder(file1)in public_ftp folder

 Give only User-sftp-vk-2 to add , modify and delete subfolder(file2) in public_ftp folder

User-Specific Configuration:

Open the SSH server configuration file using nano or vim.

Then paste this at the bottom of the file, you can modify the permission according to your need.


 Match User sftp-vk-1

ChrootDirectory /var/www/public_ftp/file1

ForceCommand internal-sftp

AllowTcpForwarding no

X11Forwarding no

Match User sftp-vk-2

ChrootDirectory /var/www/public_ftp/file2

ForceCommand internal-sftp

AllowTcpForwarding no

X11Forwarding no

In this I have given the permission to user: sftp-vk-1 to modify subdirectory file1

 and given the permission to user: sftp-vk-2 to modify subdirectory file 2