go
correo.infonavit.gob.mx has one IP number , but the reverse is correo.infonavit.org.mx. correo.infonavit.org.mx point to the same IP. infonavit.gob.mx use this as a mailserver. infonavit.gob.mx is a domain controlled by two nameservers at infonavit.gob.mx themselves. They are on the same IP network. Incoming mail for infonavit.gob.mx is handled by two mailservers also at infonavit.gob.mx. They are on the same IP network. correo.infonavit.gob.mx is hosted on a server in Mexico.

correo.infonavit.gob.mx
a records
 
+ 201.134.132.176 201.134.128.0/18 AS8151 correo.infonavit.org.mx
+ --- correo.infonavit.org.mx

infonavit.gob.mx
ns-soa records
idf.infonavit.gob.mx
+ 201.134.132.146 201.134.128.0/18 AS8151 idf.infonavit.org.mx
+ --- idf.infonavit.org.mx
ns records
idf.infonavit.gob.mx
+ 201.134.132.146 201.134.128.0/18 AS8151 idf.infonavit.org.mx
+ --- idf.infonavit.org.mx
idf2.infonavit.gob.mx
+ 201.134.132.152 201.134.128.0/18 AS8151 idf2.infonavit.org.mx
+ --- idf2.infonavit.org.mx
mx records
mail.infonavit.gob.mx
+ 201.134.132.173 201.134.128.0/18 AS8151 mail.infonavit.org.mx
+ --- mail.infonavit.org.mx
correo.infonavit.gob.mx
+ 201.134.132.176 201.134.128.0/18 AS8151 correo.infonavit.org.mx
+ --- correo.infonavit.org.mx
ip numbers of host
201.134.132.176
ptrs of ip numbers
correo.infonavit.org.mx
hostnames sharing ip with a-records
correo.infonavit.org.mx
domains using this as mailserver
infonavit.gob.mx
domains using this as mailserver under another name
infonavit.org.mx