Help Center/ Cloud Container Engine/ Best Practices/ Networking/ Optimizing CoreDNS Settings/ Client/ Optimizing Domain Name Resolution Requests
Updated on 2026-03-10 GMT+08:00
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Optimizing Domain Name Resolution Requests

DNS resolution is one of the most frequent network operations in Kubernetes clusters. Based on how DNS works in Kubernetes, you can optimize domain name resolution requests in the following ways.

Using a Connection Pool

When a container frequently communicates with another service, you are advised to use a connection pool. A connection pool caches upstream connection information, avoiding the overhead of DNS resolution and TCP connection reestablishment for each request.

Optimizing the resolve.conf File in a Container

The ndots and search parameters in resolve.conf affect the DNS resolution efficiency. For details about these parameters, see DNS Configuration.

Optimizing the Domain Name Settings

To allow a pod to access a domain name, follow these rules to minimize DNS resolution and reduce resolution latency.
  1. Accessing a Service in the same namespace: Use <service-name>, which indicates the Service name.
  2. Accessing a Service across namespaces: Use <service-name>.<namespace-name>. <namespace-name> indicates the namespace where the Service is located.
  3. Accessing an external domain name: Use an FQDN domain name. This type of domain name is specified by adding a period (.) at the end of a typical domain name to avoid multiple invalid search attempts caused by search domain combination. For example, to access www.huaweicloud.com, use the FQDN domain name www.huaweicloud.com.

Using Local DNS Cache

In large-scale clusters with high DNS resolution volume, consider caching DNS resolution results on each node. It is advised to use NodeLocal DNSCache. For details, see Using NodeLocal DNSCache to Improve DNS Performance.

Parent Topic: Client