sh8-23.1blu.de has one IP number , which also has a corresponding reverse pointer. dditb.de, jsckn.de, jsckn.net, cahit.net, niewi.net and at least 100 other hosts point to the same IP. 1blu.de is a domain controlled by two nameservers at ns1.de. They are on different IP networks. Incoming mail for 1blu.de is handled by one mailserver at 1blu.de themselves. 1blu.de has one IP number. sh8-23.1blu.de is hosted on a server in Germany.