go
airgapllc.com use this as a mailserver. dns025.a.register.com, dns053.a.register.com, dns028.a.register.com, dns076.a.register.com, dns248.a.register.com and at least 100 other hosts are subdomains to this hostname. register.com is a domain controlled by six nameservers at register.com themselves. Some of them are on the same IP network. Incoming mail for register.com is handled by two mailservers on different IP networks. register.com has one IP number.

register.com
a records
 
+ 216.21.239.101 216.21.239.0/24 AS13910  
+ ---  
ns-soa records
ns1.register.com
+ 216.21.227.10 216.21.227.0/24 AS13910  
+ ---  
ns records
ns1.register.com
+ 216.21.227.10 216.21.227.0/24 AS13910  
+ ---  
ns2.register.com
+ 216.21.227.11 216.21.227.0/24 AS13910  
ns3.register.com
+ 216.21.227.12 216.21.227.0/24 AS13910  
ns4.register.com
+ 216.21.227.13 216.21.227.0/24 AS13910  
ns5.register.com
+ 216.21.237.10 216.21.237.0/24 AS13910  
ns6.register.com
+ 216.21.237.11 216.21.237.0/24 AS13910  
mx records
smtpc.register.com
+ 216.21.224.176 216.21.224.0/24 AS13910 -
+ --- -
mail.global.frontbridge.com
+ 216.32.180.22 216.32.180.0/24 AS20046 -
domains using this as mailserver
airgapllc.com
subdomains
dns010.a.register.com
dns011.a.register.com
dns012.a.register.com
dns013.a.register.com
dns014.a.register.com
dns015.a.register.com
dns016.a.register.com
dns017.a.register.com
dns018.a.register.com
dns019.a.register.com
dns020.a.register.com
dns021.a.register.com
dns022.a.register.com
dns023.a.register.com
dns024.a.register.com
dns025.a.register.com
dns026.a.register.com
dns027.a.register.com
dns028.a.register.com
dns029.a.register.com
dns030.a.register.com
dns031.a.register.com
dns032.a.register.com
dns033.a.register.com
dns034.a.register.com
dns035.a.register.com
dns036.a.register.com
dns037.a.register.com
dns038.a.register.com
dns039.a.register.com
dns040.a.register.com
dns041.a.register.com
dns042.a.register.com
dns043.a.register.com
dns044.a.register.com
dns045.a.register.com
dns046.a.register.com
dns047.a.register.com
dns048.a.register.com
dns049.a.register.com
dns050.a.register.com
dns051.a.register.com
dns052.a.register.com
dns053.a.register.com
dns054.a.register.com
dns055.a.register.com
dns056.a.register.com
dns057.a.register.com
dns058.a.register.com
dns059.a.register.com
dns060.a.register.com
dns061.a.register.com
dns062.a.register.com
dns063.a.register.com
dns064.a.register.com
dns065.a.register.com
dns066.a.register.com
dns067.a.register.com
dns068.a.register.com
dns069.a.register.com
dns070.a.register.com
dns071.a.register.com
dns072.a.register.com
dns073.a.register.com
dns074.a.register.com
dns075.a.register.com
dns076.a.register.com
dns077.a.register.com
dns078.a.register.com
dns079.a.register.com
dns080.a.register.com
dns081.a.register.com
dns082.a.register.com
dns083.a.register.com
dns084.a.register.com
dns085.a.register.com
dns086.a.register.com
dns087.a.register.com
dns088.a.register.com
dns089.a.register.com
dns090.a.register.com
dns095.a.register.com
dns096.a.register.com
dns097.a.register.com
dns099.a.register.com
dns111.a.register.com
dns112.a.register.com
dns117.a.register.com
dns124.a.register.com
dns129.a.register.com
dns133.a.register.com
dns144.a.register.com
dns148.a.register.com
dns152.a.register.com
dns157.a.register.com
dns164.a.register.com
dns165.a.register.com
dns178.a.register.com
dns181.a.register.com
dns182.a.register.com
dns187.a.register.com
dns189.a.register.com
dns190.a.register.com
dns192.a.register.com
dns194.a.register.com
dns196.a.register.com
dns198.a.register.com
dns199.a.register.com
dns200.a.register.com
dns205.a.register.com
dns215.a.register.com
dns223.a.register.com
dns238.a.register.com
dns239.a.register.com
dns243.a.register.com
dns245.a.register.com
dns246.a.register.com
dns247.a.register.com
dns248.a.register.com
dns249.a.register.com