mx1.elb.com.br has one IP number , which also has a corresponding reverse pointer. mx1.clba.com.br, curto.elb.com.br, mx1.coelba.com.br, curto.clba.com.br, mx1.itapebi.com.br and at least two other hosts point to the same IP. elb.com.br use this as a mailserver. elb.com.br is delegated to three nameservers, however one delegated nameserver is missing in the zone and one other nameserver is listed instead. Two of them are on the same IP network. Incoming mail for elb.com.br is handled by four mailservers. Some of them are on the same IP network. mx1.elb.com.br is hosted on a server in Brazil.