Securely Transfer Files with SCP in Linux

Introduction

In Unix-like operating systems, transferring files between machines is common. One of the safest and easiest tools for this is scp (Secure Copy Protocol). scp uses SSH (Secure Shell) to move files between hosts, keeping data safe and intact. This blog will cover the basics of scp, including its syntax, common uses, and some practical examples.

What is SCP?

scp is a command-line utility that allows you to securely copy files and directories between two locations:

• From your local machine to a remote machine.

• From a remote machine to your local machine.

• Between two remote machines.

Since scp uses SSH for data transfer, it requires SSH access to the target machine. This ensures that the file transfer is encrypted, protecting your data from eavesdropping.

Basic Syntax

The basic syntax for scp is as follows:

scp [options] source_file target_file

Step-by-Step Example

Let's go through a practical example of using scp to transfer files between a local machine and a remote server.

Step 1: Create a Directory on the Remote Server

First, log in to your remote server and create a directory where you will copy the file.

shCopy codeubuntu@ip-172-31-25-99:~$ mkdir from_file
ubuntu@ip-172-31-25-99:~$ ls
from_file
ubuntu@ip-172-31-25-99:~$ cd from_file/
ubuntu@ip-172-31-25-99:~/from_file$ pwd
/home/ubuntu/from_file
ubuntu@ip-172-31-25-99:~/from_file$ exit
logout
Connection to ec2-18-117-182-251.us-east-2.compute.amazonaws.com closed.

Step 2: Use SCP to Copy a File from Local to Remote

Now, from your local machine, use the scp command to copy a file to the directory you just created on the remote server.

shCopy codehp@LAPTOP-UNNSR4CK MINGW64 ~/Downloads
$ scp -i jump-server1.pem trigle.java ubuntu@ec2-18-117-182-251.us-east-2.compute.amazonaws.com:/home/ubuntu/from_file
trigle.java                                                      100%  229     0.8KB/s   00:00

Copying a File from Remote to Local

Similarly, you can copy a file from the remote server to your local machine.

Step 1: Create a File on the Remote Server

First, log in to your remote server, create a file, and add some content to it.

shCopy codeubuntu@ip-172-31-25-99:~/from_file$ touch file.txt
ubuntu@ip-172-31-25-99:~/from_file$ echo "Hello Pratiksha" > file.txt
ubuntu@ip-172-31-25-99:~/from_file$ ls
file.txt

Step 2: Use SCP to Copy the File to Your Local Machine

From your local machine, use the scp command to copy the file from the remote server.

shCopy codehp@LAPTOP-UNNSR4CK MINGW64 ~/Downloads
$ scp -i jump-server1.pem ubuntu@ec2-18-117-182-251.us-east-2.compute.amazonaws.com:/home/ubuntu/from_file/file.txt .
file.txt                                                        100%   16     0.0KB/s   00:00

Step 3: Verify the File on Your Local Machine

After copying, check that the file is available on your local machine.

shCopy codehp@LAPTOP-UNNSR4CK MINGW64 ~/Downloads
$ ls -l file.txt
-rw-r--r-- 1 hp 197121 16 Jul 10 16:19 file.txt

Step 4: Display the File Content

Finally, display the content of the file to verify that it has been copied correctly.

shCopy codehp@LAPTOP-UNNSR4CK MINGW64 ~/Downloads
$ cat file.txt
Hello Pratiksha

Conclusion

scp is a powerful and secure tool for moving files between machines. It uses SSH to keep your data safe during transfer, making it essential for system administrators and developers. Whether you need to copy files to a remote server, get backups, or move directories, scp offers a reliable and easy solution.

By mastering scp, you can easily manage file transfers in your Unix-like environment, boosting your productivity and keeping your data secure. Try it in your next project and enjoy the ease of secure file transfer.

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