Ubuntu – SCP with two different ports

scp

How can I use scp command to copy files between two remote servers from my local PC ?

remote server 1 : IP=67.12.21.133 & port=6774

remote server 2 : IP=67.129.242.40 & port=6774

scp -rp -P 6774 denny@67.12.21.133:/home/denny/testapp1.txt denny@67.129.242.40:

It gives an error after giving password of 67.12.21.133 ,

ssh: connect to host 67.129.242.40 port 22: Connection refused

lost connection

Best Answer

You can use ~/.ssh/config to specify the ports to use for the hosts (and for setting many other nice things; check the man page man ssh_config):

# ~/.ssh/config

Host 67.12.21.133
  Port 6774

Host 67.129.242.40
  Port 6774

When doing this, you have to use the option -3 to scp, which copies the files through your local machine. Otherwise, scp issues the scp command via ssh on the first host, so it actually runs

 ssh -p 6774 denny@67.12.21.133 scp -rp /home/denny/testapp1.txt denny@67.129.242.40:

and then the ~/.ssh/config of the first remote host (67.12.21.133) is used instead of your local one.

When you have setup your ~/.ssh/config correctly, this should work:

scp -rp3 denny@67.12.21.133:/home/denny/testapp1.txt denny@67.129.242.40:

Of course, you can also copy the contents of the ~/.ssh/config file onto your first remote host, and then you can use scp without the -3 option, which will probably speeden up the transfer.

Or you can use the trick that scp uses and use such a command line:

ssh -p 6774 denny@67.12.21.133 scp -rp -P 6774 /home/denny/testapp1.txt denny@67.129.242.40:

(Note the different case of the port parameter for ssh and scp: ssh -p 6774 vs. scp -P 6774)

PS: I got this information from the OpenSSH bugzilla where I entered this as a bug: https://bugzilla.mindrot.org/show_bug.cgi?id=2020