Jim Knoble jmknoble at
Sat Mar 18 04:10:46 EST 2000

På 2000-Mar-17 klokka 10:29:44 -0500 skrivet Ben Taylor:

: On Fri, 17 Mar 2000, Mate Wierdl wrote:
: > This is the part which is not clear to me:  So in order to use scp,
: > the remote site also has to have scp.  In other words, it is not
: > enough to have just sshd running.
: if you only have sshd loaded, I think you can only do port forwarding
: and secure logins.  If you have scp, ssh, etc (on the server side),
: then you can do secure copies and secure remote shell activities.
: (I'm sure someone will correct me if I'm wrong on this)

You're mostly right.  For the following, `local' means the place one is
ssh-ing from (the ``client''), and `remote' is the place one is ssh-ing
to (the ``server'').

The following table describes what is needed at the local and remote

  Purpose                                       Local       Remote
  -------                                       -----       ------
  Execute remote shell commands or create       ssh         sshd
  interactive login sessions
  Forward X11 connections                       ssh         sshd
  Forward arbitrary TCP/IP ports, in either     ssh         sshd
  Copy files via scp                            ssh, scp    sshd, scp
As you can see, scp is needed at both ends of the session in order to
copy files (using scp).  It's possible to copy files without using scp,
using ``only'' ssh/sshd.  For example:

  cat foo |ssh 'cat >foo'

This is actually similar in principle to the way scp is used, which is
why it's the shell who complains that scp isn't found when it's not on
sshd's default path.

: The rpm is just a distribution.  I would guess that the RPM is setup so
: you don't have any extra overhead in loading the client, as opposed 
: to the server, if you will only be doing client activities.

Correct.  And the reverse as well.  The packaging scheme allows one to
install only a client or only a server if that's what's desired.

jim knoble
jmknoble at

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