How to Use SCP Command In Linux
SCP (secure copy) is a command-line utility that allows you to securely copy files and directories between two locations.
With scp
, you can copy a file or directory:
- From your local system to a remote system.
- From a remote system to your local system.
- Between two remote systems from your local system.
When transferring data with scp
, both the files and password are encrypted so that anyone snooping on the traffic doesn’t get anything sensitive.
In this tutorial, we will show you how to use the scp
command through practical examples and detailed explanations of the most common scp options.
SCP Command Syntax
Before going into how to use the scp
command, let’s start by reviewing the basic syntax.
The scp
command syntax take the following form:
scp [OPTION] [user@]SRC_HOST:]file1 [user@]DEST_HOST:]file2
OPTION
– scp options such as cipher, ssh configuration, ssh port, limit, recursive copy …etc.[user@]SRC_HOST:]file1
– Source file.[user@]DEST_HOST:]file2
– Destination file
provides a number of options that control every aspect of its behavior. The most widely used options are:
scp
-P
– Specifies the remote host ssh port.-p
– Preserves files modification and access times.-q
– Use this option if you want to suppress the progress meter and non-error messages.-C
– This option forcesscp
to compresses the data as it is sent to the destination machine.-r
– This option tellsscp
to copy directories recursively.
Before you Begin
The scp
command relies on ssh
for data transfer, so it requires an ssh key or password to authenticate on the remote systems.
The colon (:
) is how scp
distinguish between local and remote locations.
To be able to copy files, you must have at least read permissions on the source file and write permission on the target system.
Be careful when copying files that share the same name and location on both systems, scp
will overwrite files without warning.
When transferring large files, it is recommended to run the scp
command inside a screen or tmux session.
Copy Files and Directories Between Two Systems with scp
Copy a Local File to a Remote System with the scp
Command
To copy a file from a local to a remote system run the following command:
$ scp file.txt remote_username@10.10.0.2:/remote/directory
Where file.txt
is the name of the file we want to copy, remote_username
is the user on the remote server, 10.10.0.2
is the server IP address. The /remote/directory
is the path to the directory you want to copy the file to. If you don’t specify a remote directory, the file will be copied to the remote user home directory.
You will be prompted to enter the user password, and the transfer process will start.
OUTPUT
remote_username@10.10.0.2's password:
file.txt 100% 0 0.0KB/s 00:00
Omitting the filename from the destination location copies the file with the original name. If you want to save the file under a different name, you need to specify the new file name:
$ scp file.txt remote_username@10.10.0.2:/remote/directory/newfilename.txt
If SSH on the remote host is listening on a port other than the default 22 then you can specify the port using the -P
argument:
$ scp -P 2322 file.txt remote_username@10.10.0.2:/remote/directory
The command to copy a directory is much like as when copying files. The only difference is that you need to use the -r
flag for recursive.
To copy a directory from a local to remote system, use the -r
option:
$ scp -r /local/directory remote_username@10.10.0.2:/remote/directory
Copy a Remote File to a Local System using the scp
Command
To copy a file from a remote to a local system, use the remote location as a source and local location as the destination.
For example to copy a file named file.txt
from a remote server with IP 10.10.0.2
run the following command:
$ scp remote_username@10.10.0.2:/remote/file.txt /local/directory
If you haven’t set a passwordless SSH login to the remote machine, you will be asked to enter the user password.
Copy a File Between Two Remote Systems using the scp
Command
Unlike rsync
, when using scp
you don’t have to log in to one of the servers to transfer files from one to another remote machine.
The following command will copy the file /files/file.txt
from the remote host host1.com
to the directory /files
on the remote host host2.com
.
$ scp user1@host1.com:/files/file.txt user2@host2.com:/files
You will be prompted to enter the passwords for both remote accounts. The data will be transfer directly from one remote host to the other.
To route the traffic through the machine on which the command is issued, use the -3
option:
$ scp -3 user1@host1.com:/files/file.txt user2@host2.com:/files
Conclusion
In this tutorial, you learned how to use the scp
command to copy files and directories. You may also want to set up an SSH key-based authentication and connect to your Linux servers without entering a password.
If you are regularly connecting to the same systems, you can simplify your workflow by defining all of your connections in the SSH config file .
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