anchor.diff:  14.48.0		IN	PTR	tabaluga.ams.openstreetmap.org.
   15.48.0		IN	PTR	odin.ams.openstreetmap.org.
   16.48.0		IN	PTR	lockheed.ams.openstreetmap.org.
  +17.48.0		IN	PTR	norbert.ams.openstreetmap.org.
   49.48.0		IN	PTR	snap-01.ams.openstreetmap.org.
   50.48.0		IN	PTR	karm.ams.openstreetmap.org.
   52.48.0		IN	PTR	thorn-02.ams.openstreetmap.org.
  
positive.code: 14.49.0		IN	PTR	tabaluga.oob.openstreetmap.org.
  15.49.0		IN	PTR	odin.oob.openstreetmap.org.
  16.49.0		IN	PTR	lockheed.oob.openstreetmap.org.
  49.49.0		IN	PTR	snap-01.oob.openstreetmap.org.
  50.49.0		IN	PTR	karm.oob.openstreetmap.org.
  52.49.0		IN	PTR	thorn-02.oob.openstreetmap.org.
  
negative.code: 101.48.0	IN	PTR	pdu2.ams.openstreetmap.org.
  102.48.0	IN	PTR	oob1.ams.openstreetmap.org.
  
  3.49.0		IN	PTR	faffy.oob.openstreetmap.org.
  9.49.0		IN	PTR	dulcy.oob.openstreetmap.org.
  10.49.0		IN	PTR	ironbelly.oob.openstreetmap.org.
  11.49.0		IN	PTR	spike-06.oob.openstreetmap.org.
  