How to create an SFTP Server?

How to create an SFTP Server using Linux CentOS?

1.Create a dedicated sFTP group and a dedicated sFTP user. groupadd sftpusers useradd -g sftpusers -s /sbin/nologin user1 passwd user1.
2. Modify the configuration of the sshd service.
3.Create a dedicated directory for the sFTP-only user.
4.Create more sFTP-only users.

What you'll need

As I mentioned, CentOS 7 already has everything you need, out of the box. What you must have, however, is access to an account with admin rights. Once you've procured that access, it's time to make this work.

SFTP Directory
The first thing we must do is create a directory that will house our FTP data. Open up a terminal window, su to the root user (type su and then, when prompted, type the root user password), and then issue the following two commands:

mkdir -p /data/sftp
chmod 701 /data
Create the SFTP group and user
Now we're going to create a special group for SFTP users. This is done with the following command:

groupadd sftp_users
Now we're going to create a special user that doesn't have regular login privileges, but does belong to our newly created sftp_users group. What you call that user is up to you. The command for this is:

useradd -g sftp_users -d /upload -s /sbin/nologin USERNAME
Where USERNAME is the name of the user.

Next, give the new user a password. This password will be the password the new users use to log in with the sftp command. To set up the password, issue the command:

passwd USERNAME
Where USERNAME is the name of the user created above.

Create the new user SFTP directory
Now we're going to create an upload directory, specific to the new user, and then give the directory the proper permissions. This is handled with the following commands:

mkdir -p /data/USERNAME/upload
chown -R root:sftpusers /data/USERNAME
chown -R USERNAME:sftpusers /data/USERNAME/upload
Where USERNAME is the name of the new user you created above.

Configure sshd
Open up the SSH daemon configuration file with the command:

nano /etc/ssh/sshd_config
At the bottom of that file, add the following:

Match Group sftpusers
ChrootDirectory /data/%u
ForceCommand internal-sftp
Save and close that file. Restart SSH with the command:

systemctl restart sshd
Logging in
You're all set to log in. From another machine on your network that has SSH installed, open up a terminal window and issue the command:

sftp USERNAME@SERVER_IP
Where USERNAME is the name of our new user and SERVER_IP is the IP address of our SFTP server. You will be prompted for USERNAME's password. Once you successfully authenticate, you will be greeted with the sftp prompt. Type pwd to check the working path and you should see /upload (Figure A).

Figure A

Attachment 2529

Thanks for sharing your knowledge.

I had a need last year to implement a zero-cost SFTP (ftp over ssh) solution for an appliance backup to a windows server that only supported FTP over SSH.

I ended up using OpenSSH for Windows available here: http://sshwindows.sourceforge.net/

It's basically a simpler installer package consisting of the cygwin and openssh binaries but it i still a pita to configure.

The concern for this package would be the age of the OpenSSH code but it is functional and if you are only using on your internal network should be less of a concern.



There is also another windows packaged OpenSSH implementaiton that is free called copssh but I haven't played with it as of yet. But it's OpenSSH binaries are kept more up to date, currently the 5.9 codebase.. http://www.itefix.no/i2/copssh

I'm purely using the SCP functions so I can't speak for any real administration or shell capabilities of either of these.

--
Smith
Admin | Apps4Rent
Office 365 Migration | Office 365