Use Nacos with Istio to Deliver the xDS Protocol

Istio Guide

Nacos supports the CDS and EDS services in the xDS protocol and implements incremental push for EDS and MCP. You can connect Envoy or any other xDS-compatible client to Nacos to implement service discovery.

Configuration

Server

For a release package, set nacos.istio.mcp.server.enabled and nacos.extension.naming.istio.enabled in nacos/conf/application.properties to true.

For source code, set nacos.istio.mcp.server.enabled and nacos.extension.naming.istio.enabled in nacos/distribution/conf/application.properties to true.

To use the MCP incremental service, in addition to the preceding settings, set nacos.istio.server.full in nacos/istio/misc/IstioConfig to false.

Client

The following client example uses Envoy. You can download Envoy directly, or build an image and mount the following configuration files.

Config: You can change the port numbers as needed.

node:
  cluster: test-cluster
  id: test-idn

admin:
  address:
    socket_address: { address: 0.0.0.0, port_value: 15000 }

dynamic_resources:
  ads_config:
    api_type: GRPC
    transport_api_version: V3
    grpc_services:
      - envoy_grpc:
          cluster_name: nacos_xds
  cds_config:
    ads: { }
  lds_config:
    path: /etc/envoy/lds.yaml
  # ads: {}

static_resources:
  clusters:
    - type: STATIC
      connect_timeout: 1s
      typed_extension_protocol_options:
        envoy.extensions.upstreams.http.v3.HttpProtocolOptions:
          "@type": type.googleapis.com/envoy.extensions.upstreams.http.v3.HttpProtocolOptions
          explicit_http_config:
            http2_protocol_options: { }
      name: nacos_xds
      load_assignment:
        cluster_name: nacos_xds
        endpoints:
          - lb_endpoints:
              - endpoint:
                  address:
                    socket_address:
                      address: 127.0.0.1
                      port_value: 18848

lds: After the listened service obtains CDS, it actively obtains EDS from the server. You can change the listened service as needed.

resources:
  - "@type": type.googleapis.com/envoy.config.listener.v3.Listener
    name: listener_0
    address:
      socket_address: { address: 0.0.0.0, port_value: 80 }
    # listener_filters:
    # - name: "envoy.filters.listener.tls_inspector"
    filter_chains:
      - filters:
          - name: envoy.filters.network.http_connection_manager
            typed_config:
              "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
              stat_prefix: ingress_http
              access_log:
                - name: envoy.access_loggers.stdout
                  typed_config:
                    "@type": type.googleapis.com/envoy.extensions.access_loggers.stream.v3.StdoutAccessLog
              codec_type: AUTO
              route_config:
                name: local_route
                virtual_hosts:
                  - name: local_service
                    domains: [ "*" ]
                    routes:
                      - match: { prefix: "/" }
                        name: test
                        route:
                          cluster: outbound|8071||service-provider.DEFAULT-GROUP.e77d7925-1c90-4fa9-93cb-83153a099636.nacos
              http_filters:
                - name: envoy.filters.http.router

Run

Note: instances under the same service must use the same protocol. EDS uses incremental push by default.

Deploy Nacos. For deployment details, see the deployment reference.
Modify the configuration as described above.
Start the server. For detailed startup commands, see the deployment reference above.
Terminal window
```
bash startup.sh -m standalone -p embedded
```
Start the client.
Terminal window
```
docker start envoy
```

CDS Example

Note: view logs in nacos/logs/istio-main.log.

The service registered in this example uses the following configuration. For more information, see the example reference.

server.port=8071
spring.application.name=service-provider
spring.cloud.nacos.discovery.namespace=e77d7925-1c90-4fa9-93cb-83153a099636
spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848

CDS

EDS Example

The service configuration is the same as above.

EDS

Full CDS Example

#service-provider
server.port=8071
spring.application.name=service-provider
spring.cloud.nacos.discovery.namespace=e77d7925-1c90-4fa9-93cb-83153a099636
spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848
#service-consumer
server.port=8080
spring.application.name=service-consumer
spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848

Only modify the service-consumer service configuration in the console. The push result is as follows:

Full CDS

Incremental EDS Example

Only modify the service-consumer instance configuration in the console. The push result is as follows:

Incremental EDS