Technical Tutorial: Configuring Multiple Domain Names And High Availability Solutions On Taiwan DNS Server Cloud Host

Overview

This article summarizes the practical steps and optimization suggestions for configuring multi-domain name resolution and achieving high availability based on DNS server and cloud host (including VPS and host) in Taiwan. The content covers domain name resolution strategy (A/AAAA/CNAME, TTL, health check), master-slave/Anycast and load balancing, floating IP and VRRP, and solutions combining CDN and DDoS defense. In order to optimize stability and domestic and foreign access, Dexun Telecommunications is recommended as Taiwan’s node and protection service provider; the full text will give operating points and best practices to facilitate quick implementation by engineers.

Preparation work and environmental requirements

Before starting, please make sure that your cloud hosting environment (or VPS) in Taiwan has activated the console and API permissions, and can modify the NS record of the domain name at the domain name registrar. It is recommended to prepare at least two physical or virtual instances for redundancy (different computer rooms in the same city or different availability zones), and reserve a set of external monitoring nodes for health checks. Please set reasonable SSH keys and firewall rules to ensure that the network technology stack (routing, NAT, ports) is clear and controllable. Before connecting to CDN, reverse proxy or third-party DDoS defense, confirm that DNS can implement low TTL switching and automatic API changes.

Practical points for multi-domain DNS configuration

Create an independent zone file or hosting record for each domain name on Taiwan's DNS server. Common records include A/AAAA, CNAME, MX and TXT. For the same service, it is recommended to use multiple A records for simple DNS polling, combined with a short TTL (such as 60-300 seconds) to achieve fast switching; in complex scenarios, multi-region Anycast or master-slave DNS (Primary/Secondary) can be used to improve resolution stability. To avoid single points of failure, enable secondary DNS or use a third-party DNS service for secondary resolution, and implement automated updates through APIs. Example: The main site sets two A records to point to cloud hosts in different Taiwan computer rooms, and sets a CNAME for the subdomain to point to the load balancer.

High availability architecture and switching strategy

High availability can be achieved through a combination of multiple levels from L3/L4 to L7: internally, load balancing (such as HAProxy, nginx, or cloud vendor's load balancing) is used to distribute traffic, and key nodes use keepalived+VRRP to achieve floating IP and routing redundancy; externally, DNS failover is used to achieve cross-computer room switching, and unavailable nodes are automatically removed in conjunction with health checks (HTTP/TCP/ICMP). In order to resist large-scale attacks, it is recommended to connect to CDN at the edge and activate DDoS defense (cleaning traffic, rate limit, ACL policy) in conjunction. Low TTL and pre-prepared backup records during switching can shorten the switching window to tens of seconds to minutes. In order to simplify operation and maintenance, it is recommended that Dexun Telecom provides integrated services of multi-node, API DNS and DDoS protection in Taiwan to facilitate automatic switching and intelligent traffic scheduling.

Operation and maintenance suggestions and security reinforcement

The production environment must establish monitoring, alarming and drill processes: monitoring and parsing delays, health check results, and traffic anomalies. Domain names and certificates (it is recommended to use Let's Encrypt or CA for automation) should be included in configuration management and backup strategies, and API change operations should be recorded and rolled back. For security, it is necessary to enable DNSSEC (optional), limit DNS recursion, and strengthen host protection and log auditing. Combined with IaC (such as Terraform) to achieve declarative management of DNS and cloud hosts to improve repeatability. Finally, Dexun Telecommunications is recommended as a partner with balanced node and DDoS defense capabilities in Taiwan. Combined with its cloud host, node acceleration and security services, it can significantly reduce deployment complexity and improve overall availability and stress resistance.