Deploy-collector-in-cluster-mode.md

## Required of third party softwares
- JDK 6+（instruments application can run in jdk6）
- JDK8  ( skywalking collector and skywalking webui )
- Elasticsearch 5.2.2 or 5.3, cluster mode or not
- Zookeeper 3.4.10

## Download released version
- Go to [released page](https://github.com/OpenSkywalking/skywalking/releases)

## Deploy Elasticsearch server
- Modify `elasticsearch.yml`
  - Set `cluster.name: CollectorDBCluster`
  - Set `node.name: anyname`, this name can be any, it based on Elasticsearch.
  - Add the following configurations to   

```
# The ip used for listening
network.host: 0.0.0.0
thread_pool.bulk.queue_size: 1000
```

- Start Elasticsearch

### Deploy collector servers
1. Run `tar -xvf skywalking-collector.tar.gz`
2. Config collector in cluster mode.

Cluster mode depends on Zookeeper register and application discovery capabilities. So, you just need to adjust the IP config items in `config/application.yml`. Change IP and port configs of agent_server, agent_stream, ui, collector_inside, replace them to the real ip or hostname which you want to use for cluster.

- `config/application.yml`
```
cluster:
# The Zookeeper cluster for collector cluster management.
  zookeeper:
    hostPort: localhost:2181
    sessionTimeout: 100000
naming:
# Host and port used for agent config
  jetty:
    host: localhost
    port: 10800
    context_path: /
remote:
  gRPC:
    host: localhost
    port: 11800
agent_gRPC:
  gRPC:
    host: localhost
    port: 11800
agent_jetty:
  jetty:
    host: localhost
    port: 12800
    context_path: /
agent_stream:
  default:
    buffer_file_path: ../buffer/
    buffer_offset_max_file_size: 10M
    buffer_segment_max_file_size: 500M
ui:
  jetty:
    host: localhost
    port: 12800
    context_path: /
# Config Elasticsearch cluster connection info.
storage:
  elasticsearch:
    cluster_name: CollectorDBCluster
    cluster_transport_sniffer: true
    cluster_nodes: localhost:9300
    index_shards_number: 2
    index_replicas_number: 0
    ttl: 7
```


3. Run `bin/startup.sh`