Using Java chassis for cross data center access

Now that you’ve seen two multiple data center architectures of the Service Center, we’ll show you how to implement micro-service cross data center access with the java-chassis framework.

architecture

architecture

Quick Start

Let’s assume you want to install 2 clusters of Service-Center in different DCs with following details.

Cluster Datacenter Address
sc-1 dc-1 10.12.0.1
sc-2 dc-2 10.12.0.2

Start Service-Center

Edit the configuration of the ip/port on which SC will run in dc-1. And here we assume your etcd is running on http://127.0.0.1:2379 (you can follow this guide to install etcd in cluster mode.)

vi conf/app.conf
# Replace the below values
httpaddr = 10.12.0.1
discovery_plugin = aggregate
aggregate_mode = "etcd,servicecenter"
manager_name = "sc-1"
manager_addr = "http://127.0.0.1:2379"
manager_cluster = "sc-1=http://10.12.0.1:30100,sc-2=http://10.12.0.2:30100"

# Start the Service-center
./service-center

Notes: + manager_name is the alias of the data center. manager_addr is the etcd cluster client urls. manager_cluster is the full Service Center clusters list. + To deploy Service Center in dc-2, you can repeat the above steps and just change the httpaddr value to 10.12.0.2.

Confirm the service is OK

We recommend that you use scctl, and using cluster command which makes it very convenient to verify OK.

scctl --addr http://10.12.0.3:30100 get cluster
#   CLUSTER |        ENDPOINTS
# +---------+-------------------------+
#   sc-1    | http://10.12.0.1:30100
#   sc-2    | http://10.12.0.2:30100

Example

Here we show a java example of multiple datacenters access, where we use an example, assuming that below.

Microservice Datacenter Address
Client dc-1 10.12.0.4
Server dc-2 10.12.0.5

Start springmvc-server

Edit the configuration of the ip/port on which springmvc-server will register.

vi src/main/resources/microservice.yaml

Replace the below values

cse:
  service:
    registry:
      address: http://10.12.0.2:30100 # the address of SC in dc-2

Run the Server

mvn clean install
java -jar target/springmvc-server-0.0.1-SNAPSHOT.jar

Start springmvc-client

Edit the configuration of the ip/port on which springmvc-client will register.

vi src/main/resources/microservice.yaml

Replace the below values

cse:
  service:
    registry:
      address: http://10.12.0.1:30100 # the address of SC in dc-1

Run the Client

mvn clean install
java -jar target/springmvc-client-0.0.1-SNAPSHOT.jar

Confirm the multiple datacenters discovery is OK

Since springmvc-client is not a service, we check its running log.

...
[2018-10-19 23:04:42,800/CST][main][INFO]............. test finished ............ org.apache.servicecomb.demo.TestMgr.summary(TestMgr.java:83)