Nacos — Dynamic Service Discovery & Config Management

What it is

Nacos (Naming And Configuration Service) is an Alibaba-incubated, Apache 2.0 licensed platform that combines service registry, dynamic configuration, and service management. It targets the same problems as Eureka, Consul, and Spring Cloud Config but bundles them into a single server with one console and one SDK.

It is designed for teams building microservices with Spring Cloud, Dubbo, gRPC, or Kubernetes who need a centralized place for service discovery and configuration hot-reload.

How it saves time or tokens

Running separate systems for service discovery (Eureka or Consul) and configuration (Spring Cloud Config or etcd) increases operational overhead. Nacos consolidates both into one process with one admin console. Dynamic configuration with namespace isolation and version history means developers push config changes without restarting services. The built-in health check system detects unhealthy instances and routes traffic away automatically.

How to use

1. Start a standalone Nacos server with Docker.

docker run -d --name nacos -p 8848:8848 -p 9848:9848 \
  -e MODE=standalone nacos/nacos-server:v2.4.3

1. Open the console at http://localhost:8848/nacos (default credentials: nacos/nacos).

1. Register a service programmatically.

curl -X POST 'http://127.0.0.1:8848/nacos/v1/ns/instance?serviceName=demo&ip=10.0.0.1&port=8080'

Example

Publishing and reading a configuration key:

# Publish config
curl -X POST 'http://127.0.0.1:8848/nacos/v1/cs/configs' \
  -d 'dataId=app.properties&group=DEFAULT_GROUP&content=db.url=jdbc:mysql://localhost:3306/mydb'

# Read config
curl 'http://127.0.0.1:8848/nacos/v1/cs/configs?dataId=app.properties&group=DEFAULT_GROUP'

Spring Boot apps using nacos-config-spring-boot-starter pick up changes automatically without restart.

Related on TokRepo

• DevOps tools -- Infrastructure tools for cloud-native service management.
• Self-hosted tools -- Run your own service discovery and config management.

Common pitfalls

• Standalone mode uses embedded Derby. For production, configure an external MySQL backend for high availability.
• Nacos 2.x uses gRPC on port 9848 in addition to HTTP on 8848. Ensure both ports are open in your firewall rules.
• The default credentials (nacos/nacos) must be changed before exposing the console to any network beyond localhost.