topic Re: sftp - Protocol major versions differ in Operating System - Linux

sftp - Protocol major versions differ

joseph wholey — Thu, 23 Mar 2006 09:50:15 GMT

I'm attempting to sftp from a RHEL AS3 server to an AIX 4.3 maching and am getting the following message:
"Protocol major versions differ: 2 vs. 1
Couldn't read packet: Connection reset by peer"
However, my versions of sftp are not different. Please view the output of ssh -V:
RHEL: OpenSSH_3.6.1p2, SSH protocols 1.5/2.0, OpenSSL 0x0090701f
AIX: OpenSSH_3.0.2p1, SSH protocols 1.5/2.0, OpenSSL 0x0090603f

Any ideas why this would be happening? thx.

Re: sftp - Protocol major versions differ

Steven E. Protter — Thu, 23 Mar 2006 09:56:20 GMT

Shalom joseph,

The AIX version is extremely old and known to have a lot of bugs.

It should be upgraded.

The RH version is more current, but openssh is at 4.2 right now.

I think your results will be much better if the two versions were based on versions of openssh that were closer togther.

SEP

Re: sftp - Protocol major versions differ

Bill Thorsteinson — Thu, 23 Mar 2006 13:58:55 GMT

Check your ssh configuration files for
Red Hat. Protocol is likely set to 2 only.

Check your ssh configuration files for AIX
Likely set to 1 only. This is not secure.
Change to 2 only.

The line for protocol should be
Protocol 2
on both servers. There are two files;
ssh_config and sshd_config. All four
configuration files should have this line.

You may aldo be missing the keys for SSH 2
on on of the servers.

Try ssh -v to see what is being negotiated.

Re: sftp - Protocol major versions differ

Antonio Cardoso_1 — Fri, 24 Mar 2006 16:36:38 GMT

Hi Joseph,

If you cannot configure your AIX SSH server to accept protocol version 2, you still can configure the SSH client on your RHEL.
Copy /etc/ssh/ssh_config to $HOME/.ssh/config, and set Protocol option to :
Protocol 2,1

this will first try v2, and if fails will fall back to v1.

V1 is not so sure as v2, but still better than telnet!!