I started having problems with my DeltaCopy (rsync 3.0.5 on Windows). ssh with a "i" key works fine. The error is as follows:

C:\Program Files\Synametrics Technologies\DeltaCopy>rsync -a -vvv --log-file=a.l
og cygz.dll -e "ssh -l root -p 5050" myhost:/test/
opening connection using: ssh -l root -p 5050 myhost rsync
--server -vvvlogDtpre.iLs . /test/
Cannot connect to the host
rsync: read error: Connection reset by peer (104)
rsync error: error in rsync protocol data stream (code 12) at /home/lapo/packagi
ng/rsync-3.0.4-1/src/rsync-3.0.4/io.c(791) [sender=3.0.4]
_exit_cleanup(code=12, file=/home/lapo/packaging/rsync-3.0.4-1/src/rsync-3.0.4/i
o.c, line=791): about to call exit(12)


When I try to insert the key into ssh command I got the following:
C:\Program Files\Synametrics Technologies\DeltaCopy>rsync -a -vvv cygz.dll -e "ssh -l root -p 22 -i backupkey" myhost:/test/

opening connection using: ssh -l root -p 22 -i backupkey myhost.
co.uk rsync --server -vvvlogDtpre.iLs . /test/
Cannot resolve host 'backupkey'
rsync: read error: Connection reset by peer (104)
rsync error: error in rsync protocol data stream (code 12) at /home/lapo/packagi
ng/rsync-3.0.4-1/src/rsync-3.0.4/io.c(791) [sender=3.0.4]
_exit_cleanup(code=12, file=/home/lapo/packaging/rsync-3.0.4-1/src/rsync-3.0.4/i
o.c, line=791): about to call exit(12)

Rsync works fine from another Linux PC. I have tried to disable the firewall and different internet connections.
The rsync version on my windows is 3.0.5 and I also tried to downgrade it on the Linux to 2.6.9

Anyone knows how to cure this problem? Out of blue rsync just stopped working. I am running CentOS with latest updates....

That section pops out at me first; you may to check your syntax as it appears to be attempting to use "backupkey" as the hostname.

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Yeah, I have seen this one as well and I do not understand. Its either connection has been reset by peer or cannot resolve host "sshkey"...

I have checked it many times - the syntacsis is ok. Ssh is working ok if I issue a command "ssh myhost -l root - i sshkey"...

Since I'm not familiar with the product you are using, and thus don't have any directly useful suggestions for configuring it, I have a couple of alternate paths you could take.

If running rsync on Windows in order to interface with your VPS is a requirement, I recommend Cygwin (http://www.cygwin.com/) as the environment of choice. Otherwise, have you considered th alternate approach of installing something like Sun xVM and doing it inside a minimal Debian (or your distro of choice) install? I use VMs for backup purposes, and it's worked out well for me.

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rsync.exe I have is a part of Cygwin.

Sun xVM...probably worth trying. I just do not get it why this rsync error comes up. I think it could be due to some Windows updates were installed. BTW, I do not see any rsync connection to the server on the server side.

Since you mentioned updates, any chance that changes to your local workstation or LAN firewall config could be blocking the connection?

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Just an update; rsync in Cygwin gives me the same error:

Cannot connect to the host
rsync: read error: Connection reset by peer (104)

Any idea why this may happen?

This is what I have thought. But I can still connect to Linode via ssh!!!
Also I have tried to stop Windows Firewall service. No luck...

Another update
Command rsync -v -a -z file.exe root@myhost
is copying file into a local directory under name root@myhost....

as soon as I put root@myhost:/backup is says

Cannot connect to the host.

At this point I'd recommend taking a look at reinstalling your client-side software. Given the fact that known past good commands (according to your assertions) are failing, I think you might be dealing with a corrupted local environment. Although I must also add that not putting the protocol or full remote path before the last argument in a command is not likely to work, as it will treat that argument as a local file instead of a remote destination.

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Has your local net connection's IP changed recently? In other words, do you have firewall rules in place on the CentOS VPS to only allow connections from specific IPs (I certainly do)?

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I have tried to reinstall the software. The same result. I think I need to reinstall Windows. I just do not wanna do that just because of rsync.

No, CentOS firewall blocks certain ports only. Currently, I tried to disable it, again no luck. Also I have tried to rsync to another server.
The same result.

I just wonder how I can debug rsync on Windows?

I'd attempt to duplicate the problem on another machine with a similar software environment. Do you have another box you can test from?

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