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Hi I've got a problem trying to Rsync a backup to another server. I get the error

Address xxxxxxx maps to xxxxxxx, but this does not map back to the address - POSSIBLE BREAK-IN ATTEMPT!

The first xxxxxxxxx is the correct IP but the second is a website and lord knows where that has come from is there any way around this problem?

I'm on a linux box in both accounts, just command line only.

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up vote 0 down vote accepted

reverse dns is fun. the "website" you mentioned is probably your ISPs reverse DNS record. usually something like or some such. You can hush that error up by adding an entry in the remote side's "hosts" (/etc/hosts) file by specifying an entry specifically for that IP... i.e.


For more info... here's a good article on that:

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Thanks for your help, I have to say thanks from the bottom of my heart! I've been talking to the 2 companies who are meant to help me sort these 2 servers out and none have helped - at last a straightforward answer! – Richard Housham Jan 9 '12 at 10:41

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