keyset-in-addr.arpa.

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$ORIGIN .
in-addr.arpa		604800	IN KEY	256 3 1 (
					AQPwQ09X107YyGnIwU/Wb0Xa5EdWPvcvevyU
					kqATItaf8hqqXlxYYtAzyCZSF+HH+RZnesjD
					mzfi4jtXFitVyYV/
					) ; key id = 51589