It is common to configure multiple DNS answers (i.e., responses) within a given domain name and record type. Due to the behavior of public resolvers, this can offer a very simple "round-robin"-type configuration. However, using the NS1 Filter Chain™, you can configure advanced, customized traffic routing logic to meet your specific needs. NS1 offers more than 20 filters — each designed to process a list of answers within a DNS record differently. You can "chain" multiple filters together to achieve a specific outcome.
A typical use case is if you have multiple web servers (each with a different IP address) that must serve traffic for a given domain. Say, for example, you have a domain, www.example_zone.com, and you want to send traffic to three IP addresses: 18.104.22.168, 22.214.171.124, and 126.96.36.199. Follow the steps below to configure multiple answers in NS1 Connect:
Navigate to DNS > Zones to view a list of zones associated with your account.
Click the name of the zone (e.g., example_zone.com) to drill down into the zone details, including a list of associated records.
In the Records tab, scroll to the bottom of the screen and click Add record.
Set the desired record type (A), domain (www.example_zone.com), and TTL (default is 3600 seconds).
Under Answers, enter the first answer (188.8.131.52) in the space provided, and then click Add answer. Add subsequent answers to the record, clicking Add answer for additional fields as desired. Once complete, click Save record.
If you perform a DNS lookup for the domain (e.g., dig A @dnsX.pYY.nsone.net www.example_zone.com) where "dnsX.pYY.nsone.net" is one of the name servers listed under the Nameservers tab in your zone, you receive all three answers in the response.
Another common example is configuring an MX (mail exchange) record within a zone, specifying answers for multiple mail servers — each with a different priority value.
For example, maybe you want to set MX for example_zone.com to mail1.example_zone.com with priority 1 (higher) and mail2.example_zone.com with priority 5 (lower).
Select MX record type and set the domain and TTL. Under Answers, enter your answers, clicking Add answer for additional fields as desired. Since this is an MX record, you will be prompted to enter a priority value with each mail server.
Click Save record and perform a query on the new record type (dig MX @dnsX.pYY.nsone.net example_zone.com), and you see both answers.