I'm trying to sync my remote web folder with my local one
$ rsync -navz -e ssh remoteuser@remotehost:www/domain /var/www/html

I am prompted for the password.
remoteuser@remotehost's password:
After I enter the password I get

protocol version mismatch - is your shell clean?
(see the rsync man page for an explanation)
rsync error: protocol incompatibility (code 2) at compat.c(69)

$ which ssh returns /usr/bin/ssh
ssh is working

My rsync version is 2.6.2-0.
My kernel is 2.6.5-1.358 with Fedora Core 2.
My host's remote kernel is 2.4.29-2-s5

What can I do?

There is probably a script producing output in your .bash_profile or similar file (fortune, perhaps?).

Try this as a test:
You should see NO results after entering the password.

Well, no, there is no output when I do that at shell.
If I do
$ rsync -navz -e ssh remoteuser@remotehost:www/domain 2>/dev/null /var/www/html
I am prompted for the password, but when I enter it I am back to my local shell, as if the connection were instantaneously dropped!

2>/dev/null would supress any rsync errors.

Matir,
Thank you, but I can't connect nevertheless.
I read .bash_profile and even in my extreme ignorance I don't see anything bizarre.
The same for .bashrc

P.S.
Not that it adds to the description of the problem, but I used the last putty version from a Windows box and there was no incompatibility. But I can only afford to do this in Linux.

My host suppressed the welcome message that interfered with rsync by changing my shell at the server.
Done!

It should be noted that if you are using passwordless ssh (via certificate), there may be further issues to look at. If the backup account's authorized_keys file (in ~/.ssh) has more than just the ssh-rsa or ssh-dsa line, that is, if it contains a ``command="rsync --server --daemon'' prefix to the ssh-rsa / ssh-dsa line, that could very well be triggering the message, "protocol version mismatch - is your shell clean?"

I've been using bontmia for rsync backups, and it is a great script. However, it seems to expect a clean authorized_keys file, without a ``command=...'', and doesn't say so in the instructions.

Just thought I'd point that out.

-plaus

Sorry if this was posted twice. When I clicked on "Submit Reply" something went wrong and my browser crashed.

I am having similar problem.
I have 2 system that act as firewalls, one is the backup of another so they are identical.

I use command="rsync --server --daemon ." in the authorized_keys2 file and it works without any problem.

I am trying to do the same with my devlopment and production web server which have different versions of rsync. If I remove
command="...." from the ssh key, the rsync from develpoment to production works. When I add command="rsync --server --daemon ." to the file I get following error:

protocol version mismatch - is your shell clean?
(see the rsync man page for an explanation)
rsync error: protocol incompatibility (code 2) at compat.c(62)

Do you have to have same version of rsync in order to use server protocol?

Following command creates empty file so I do not think the startup file is problem.

ssh -i ~/.ssh/rsync.dsa root@prodsys true > /tmp/x

Development system is using:
# rsync -h
rsync version 2.5.6 protocol version 26

Production is using:
# rsync -h
rsync version 2.6.2 protocol version 28

What is the protocol version is that a problem?

On development system I run following command:

# rsync -rLptgz -e "/usr/bin/ssh -i ~/.ssh/rsync.dsa" /var/www root@prodsys:/var/www

On production system I have command="rsync --server --daemon ." in the authorized_keys2 file.

Hey all,

I found this thread here looking for the same problem. In reading this I had an epiphany. I asked myself what has changed since this was working before... what an odd thing to do :P

I use rsync with ssh and authorized key files for auto login to mirror a remote system to the local one.

The only change I made was on my .bashrc on the remote end I added in some commands to show file system usage. do a du -f and a tail of the log on login for conveniences.

My assumption here is that when rsync executes the ssh to connect it received 'junk'. Once I removed the extra output from the .bashrc file on the remote end, it worked just fine.

SO check your remote end for .profile, .bashrc, .bash_profile etc.... any scripts running that add extra output on login.

Just ask for any questions!

Cheers,
#Ian.

I'm getting this "protocol version mismatch" error even when I tried to rsync files on the same server.

---------------------
[root@ ~]# rsync -av /home/mohammed/scptest mohammed@localhost:./test/
mohammed@localhost's password:
protocol version mismatch -- is your shell clean?
(see the rsync man page for an explanation)
rsync error: protocol incompatibility (code 2) at compat.c(171) [sender=3.0.6]
[root@ ~]#
---------------------

rsync version 3.0.6 protocol version 30
CentOS release 5 (Final)


I checked .bash* files, I don't see any junk inputs there.

Any ideas??

Got an answer <but yet to find a permanent fix for me>

For my customized setup, I had added two commands to /etc/bashrc which apparently confused rysnc. Rsync is working without my additional lines. It looks like any modifications to /etc/bashrc hurts rsync.

The problem is, I can't exclude those two commands from executing when I user logs in. Since they are MUST RUN commands, I am searching for alternatives.

I welcome any suggestions on this.

Thanks,
Mohammed

Got through when I added my commands to /etc/profile instead of /etc/bashrc. As far I checked, it's working fine. I'll let you know if I find any issues.

~mohammed

3 members found this post helpful.

Thanks mohammednv!

Removing output from my remote host's .bashrc file solved my issues connecting to the remote host via rsync, sftp, and scp. (I had a informational echo statement, which is now removed.)

-Jon

Thank you mohammednv!