How do I change the DNS servers of a node?

Pextra CloudEnvironment® uses CoreDNS for cluster DNS resolution. External DNS queries are forwarded to upstream DNS servers. To change the upstream DNS servers used by nodes, create a CoreDNS drop-in configuration to override the default upstream servers:

1. Create a drop-in file with the following format under /etc/coredns/conf.d/:

   echo "forward . <DNS_SERVER_1> <DNS_SERVER_2> <DNS_SERVER_N>" > /etc/coredns/conf.d/custom-upstream.conf
   

   Example:

   echo "forward . 192.0.2.1 192.0.2.2" > /etc/coredns/conf.d/custom-upstream.conf
   

2. Apply the CoreDNS configuration change.

   systemctl reload coredns
   

Note

Up to 15 DNS servers can be specified in the forward rule.

Default Upstream Servers

The following default fallback servers are used if no upstreams are configured:

• 9.9.9.9 (Quad9)
• 1.1.1.1 (Cloudflare)
• 8.8.8.8 (Google)

Reference

For advanced configuration, see https://coredns.io/plugins/forward/.