ns4.rax.ru has one IP number , but the reverse is ns8.nic.ru. ns4.li.ru, ns2.ogl.ru, ns3.rus.ru, ns8.nic.ru, ns8.ripn.ru and at least 27 other hosts point to the same IP. rax.ru use this as a nameserver. rax.ru is a domain controlled by four nameservers at rax.ru themselves. Two of them are on the same IP network. Incoming mail for rax.ru is handled by one mailserver also at rax.ru. rax.ru has one IP number. ns4.rax.ru is hosted on a server in Russian Federation.