If you are using a redhat 6 or one of it's clients check if you're using selinux.  If so configure it's policies to allow ssh with keys loggin or put it in permissive mode.
Check redhat documentation for details.
Pedro Oliveira

On Oct 10, 2012 6:25 PM, "Robert E. Wooden" <rbrtewdn@comcast.net> wrote:
I have been using Backuppc for a few years now. Recently I upgraded my machine to newer, faster hardware. Hence, I have experience exchanging ssh keys, etc.

It seems I have one client that refuses to connect via ssh. When I exchanged keys and ran "ssh -l root [clientip] whoami" the client properly returns 'root'. When I "sudo -u backuppc /usr/share/backuppc/BackupPC_dump -v -f [clienthostname]" I get 'dump failed: Unable to read 4 bytes'.

I have checked versions of rsync, ssh and openssh-server on both the backuppc machine and the client. They are the same on both (both running Ubuntu 12.04LTS.)

I have tailed the clients auth.log file it shows "sshd[10109]: Connection closed by [backuppc-ip] [preauth]" so, the backuppc machine is closing the connection. (I might be tailing the wrong file, I am not sure.)

Why won't this client connect?
Robert Wooden
Nashville, TN. USA

Computer Freedom? . . . Linux

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