I would like to backup my computer with rsync regulary with cron to a linux server. Both computer are running with debian.
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The sshkey requires a password but I use ssh-add to activate the key. The key is also at the server.
I don't think ssh-add will do, you really do need to make the key passwordless. At least I had that problem. I was logging in from a machine with ssh-agent (or rather, the PuTTY equivalent) running and everything worked fine. But the same operations wouldn't work from the crontab.
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it generates the following output: Permission denied, please try again. Permission denied, please try again. Permission denied (publickey,password,keyboard-interactive). rsync: connection unexpectedly closed (0 bytes read so far) rsync error: error in rsync protocol data stream (code 12) at io.c(165)
You may want to increase the SSH verbosity with '-v' options. That may tell you what it is trying to do, when it gets the 'Permission denied' errors. That may or may not help you.
Cheers, Tobias