Custom Name Server Addresses – In compliance with standard RFCs, each name server must run on two unique IP addresses. In order for resellers and other customers to utilize custom name servers on their own domain, 2 IP addresses are required.
上面是我复制别人的发客服,
下面是客服回答.
Hello,
Thank you for contacting us! Due to the IPv4 exhaustion we must be judicious in giving out additional IPv4 addresses and require technical justification to do so. Technical justification meaning it is impossible to accomplish the task without an additional IPv4 address. Hosting two name servers on your Linode with different IP addresses will not create DNS redundancy as both servers will go down if your Linode losses connectivity. Due to this issue, we will not allocate an additional IPv4 address at this time. Please let us know if you have any questions.