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Questions[sftp](server)

Martin Hope
Tommy B.
Asked: 2012-01-29 12:40:47 +0800 CST
  • 109

I'm starting a very little hosting company for a few friends and little clients, nothing big.

I want to give my "clients" the right to manage their files on the server. I hate FTP as it is not secure and it's in my opinion obsolete.

So I'd like to allow my users to connect through SFTP but not allow them to connect through SSH. (I know, I know, SFTP is using SSH). But I was just wondering, is it possible?

So I wouldn't have to install a FTP service on the server and everything would be awesome!

linux centos ftp sftp
Martin Hope
Adi Roiban
Asked: 2011-05-27 00:02:39 +0800 CST
  • 49

The Openssh ssh and scp command provied an -i command line option to specify the path to the RSA/DSA key to be used for authentication.

Looking at the sftp man pages I was not able to find a way to specify the RSA/DSA key.

I am looking for a way to do initiate an sftp session that will use a specified RSA/DSA key, and not the ~/.ssh/id_{dsa,rsa} keys.

I tried OpenSSH sftp client on Linux...but it should have the same options on other platforms.

ssh sftp rsa dsa
Martin Hope
Tom Feiner
Asked: 2010-04-26 03:07:29 +0800 CST
  • 74

Rsync over ssh, works great every time.

However, trying to rsync to a host which allows only sftp logins, but not ssh logins, provides the following error:

rsync -av /source ssh user@remotehost:/target/

protocol version mismatch -- is your shell clean? (see the rsync man page for an explanation) rsync error: protocol incompatibility (code 2) at compat.c(171) [sender=3.0.6]

Here's the relevant section from the rsync man page:

This message is usually caused by your startup scripts or remote shell facility producing unwanted garbage on the stream that rsync is using for its transport. The way to diagnose this problem is to run your remote shell like this:

          ssh remotehost /bin/true > out.dat

then look at out.dat. If everything is working correctly then out.dat should be a zero length file. If you are getting the above error from rsync then you will probably find that out.dat contains some text or data. Look at the contents and try to work out what is producing it. The most com‐ mon cause is incorrectly configured shell startup scripts (such as .cshrc or .profile) that contain output statements for non-interactive logins.

Trying this on my system produced the following in out.dat:

ssh-dummy-shell: Command not allowed.

As I thought, the host is not allowing ssh logins.

The following link shows that it is possible to accomplish this task using fuse with sshfs - however it is extremely slow, and not fit for production use.

Is there any chance of getting rsync sftp to work?

ssh rsync sftp