Subject: Re: inetd.conf defaults
To: Jasper Wallace <>
From: Andrew Brown <>
List: tech-net
Date: 05/30/2000 15:01:31
>The choice is between:
>a) NetBSD with no ssh support - everyone has to install ssh from pkgsrc
>b) NetBSD with ssh v.2 support - some people have to install ssh v.1 from
>   pkgsrc. (we could even ship with an install-ssh-1 script that worked
>   without pkgsrc support).
>b) is an improvement over a).

actually, it's not.  version 1 clients and servers interoperate well,
of course.  the same goes for version 2 clients and server.  the
"backwards compatibility doesn't work.

if you run ssh (version 2) to connect to a machine which is version 1,
ssh (version 2) will exec ssh1 (if possible) for you so that you can

likewise, if you run ssh (version 1) and connect to a version 2
server, the version 2 server will exec sshd1 (again, if possible) for
you, so that you can connect.

the problem is with scp.  scp (version 2) calls ssh (version 2) to
connect to the remote machine (which is version 1 and i, as the
client, will have to step back).  ssh (version 2) execs ssh1 in order
to talk to the remote server (which is version 1), but scp (version 2)
has no idea this happened.  ssh1 connects and establishes a secure
channel, and then ssh1 sends the scp (version 2) command line (like
rcp).  the problem is that scp version 1 and scp version 2 have
*incompatible* command line options.  the copy fails.

not quite backwards compatible.

|-----< "CODE WARRIOR" >-----|             * "ah!  i see you have the internet (Andrew Brown)                that goes *ping*!"       * "information is power -- share the wealth."