Usage of a telnet client instead of ssh or rsh

[Mike Daws]

On Sat, 2006-05-13 at 20:53 +0100, Jamie Lokier wrote:
> Jan-Benedict Glaw wrote:
> > On Sat, 2006-05-13 20:27:03 +0200, Paul Slootman <paul at debian.org> wrote:
> > > On Fri 12 May 2006, Matt McCutchen wrote:
> > > > Wayne beat me to it.  But I was going to say, you might be able to write
> > > > a wrapper script that sends the rsync command and arguments down the
> > > > telnet connection for the shell to execute and discards any extra output
> > > > produced by the shell while logging in (to avoid the mystifying "is your
> > > > shell clean?" message).  For instance, if you know the shell on the
> > > 
> > > Don't forget also that there is actually such a thing as a telnet
> > > protocol, so a telnet session probably won't give you a real clean
> > > connection, some combination of special bytes may trigger telnet to do
> > > unexpected things instead of passing the data on transparently.
> > > 
> > > Is there no way of using rsh in your kerberos-ized situation?
> > 
> > Well, ignoring the protocol-specific extensions, I'd think of some
> > kind of expect(1) wrapped telnet client to do the login and
> > command-sending stuff...
> > 
> > Though that's all a crude workaround. Why don't you just use ssh,
> > which is nicely (via GSSAPI) kerberized?
> 
> ssh isn't always an option.  E.g. to reach HP's testdrive machines,
> telnet is the only available option.
> 
> I've done rsync over telnet, in binary mode and with the terminal set
> to raw, using Perl and the Perl Net::Telnet module, and it mostly
> worked but there were sometimes errors.

netcat ( nc(1) ) should bypass the telnet protocol issues.