go
mail.nukleuz.com and mail.nukleuz.co.uk point to 87.194.122.32.

mail.nukleuz.co.uk
a records
 
+ 87.194.122.32 87.194.96.0/19 AS35228  
+ ---  

mail.nukleuz.com
a records
 
+ 87.194.122.32 87.194.96.0/19 AS35228  
+ ---  
ip numbers of host
87.194.122.32
hostnames sharing ip with a-records
mail.nukleuz.co.uk
mail.nukleuz.com
domains using this as mailserver
nukleuz.co.uk
nukleuz.com