scp to this one host fails

bluethundr · 04-11-2010, 12:05 AM

If I attempt to SCP any file (like say, my public RSA key) to my home server I am dumped into a non-interactive bash prompt and the transfer fails. I have looked at the output of the -vvv option to SCP and included it with this post. Nothing about this failure is jumping out at me and a fresh analysis would be appreciated.

Code:

bluethundr@walmac~:scp ~/.ssh/id_rsa.pub bluethundr@$HOMEIP:/home/bluethundr
bluethundr@xx.xx.xxx's password: 
This shell is not interactive
bluethundr@walmac~:

And this is my .bashrc on my local host from which I scp.

Code:

export HOMEIP=xx.xxx.xx.xxx
export PS1="\u@\h\W:"
ENV=~/.env
export ENV
. $ENV

this is the .bashrc on the host i try to scp to:

Code:

# .bashrc 
# Source global definitions
if [ -f /etc/bashrc ]; then
        . /etc/bashrc
fi
 
# User specific aliases and functions
if [ -z "$PS1" ]; then
             echo This shell is not interactive
     else
             echo This shell is interactive
fi
 
 
PATH=$PATH:$HOME/bin:/usr/local/bin:/usr/local/lib/:/usr/kerberos/sbin:/usr/kerb
eros/bin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/NX/bin
 
export PATH

Lexus45 · 04-11-2010, 04:45 AM

is the sshd on the $HOMEIP running?
is bluethundr user allowed to log in via ssh ?

bluethundr · 04-11-2010, 11:20 AM

yes, ssh works. just not allowed to scp for some bizarre reason:

Code:

[bluethundr@cloud1 ~]$ ssh bluethundr@$HOMEIP
bluethundr@xx.xx.xx.xxx's password: 
Last login: Sun Apr 11 12:21:06 2010 from ec2-184-73-184-128.compute-1.amazonaws.com
#########################################################
#               SUMMITHOME.COM                          #
#               TITLE:       LCENT5-1 BOX               #
#               LOCATION:    SUMMIT BASEMENT            #
#                                                       #
#########################################################


This shell is interactive
-bash-3.2$

:

colucix · 04-11-2010, 11:35 AM

What if you remove the echo statements from the remote .bashrc? Is the file copied in that case?

bluethundr · 04-11-2010, 11:49 AM

yep! removing those echo statements from .bashrc (which I reference in the first post) cleared up the issue! Thanks! Any clue on why those statements would muck up scp and not ssh? ::shrug::

colucix · 04-11-2010, 12:03 PM

You're welcome! Actually I didn't ever understand if this is an unresolved bug or an expected behavior. Anyway, it is reported in the openssh FAQ, here and involves non-interactive shells.

Indeed, if you need to receive some output from the remote .bashrc upon login sessions, you can do something similar to your original script: just exit if non-interactive OR don't send output OR invert the logic, e.g.

Code:

if [ -n "$PS1" ]
then
  echo Welcome!
fi

Moreover, non-interactive bash sessions don't execute .bash_profile, so that it is a good place for echoing messages or executing commands that write to standard output.