PD

PD is the abbreviation for Placement Driver. It is used to manage and schedule the TiKV cluster.

PD supports distribution and fault-tolerance by embedding etcd.

Build

1. Make sure ​Go​ (version 1.5+) is installed.
2. Use make build to install PD. PD is installed in the bin directory.


Usage

PD ports

You can use the following default ports in PD:

• 1234: for client requests with customized protocol.
• 9090: for client requests with HTTP.
• 2379: for embedded etcd client requests
• 2380: for embedded etcd peer communication.

You can change these ports when starting PD.

Single Node with default ports

# Set correct HostIP here. 
export HostIP="192.168.199.105"

pd-server --cluster-id=1 \
          --host=${HostIP} \
          --name="pd" \
          --initial-cluster="pd=http://${HostIP}:2380" 

The command flag explanation:

• cluster-id: The unique ID to distinguish different PD clusters. It can't be changed after bootstrapping.
• host: The host for outer traffic.
• name: The human readable name for this node.
• initial-cluster: The initial cluster configuration for bootstrapping.

Using curl to see PD member:

curl :2379/v2/members

{"members":[{"id":"f62e88a6e81c149","name":"default","peerURLs":["http://192.168.199.105:2380"],"clientURLs":["http://192.168.199.105:2379"]}]}

A better tool httpie is recommended:

http :2379/v2/members
HTTP/1.1 200 OK
Content-Length: 144
Content-Type: application/json
Date: Thu, 21 Jul 2016 09:37:12 GMT
X-Etcd-Cluster-Id: 33dc747581249309

{
    "members": [
        {
            "clientURLs": [
                "http://192.168.199.105:2379"
            ], 
            "id": "f62e88a6e81c149", 
            "name": "default", 
            "peerURLs": [
                "http://192.168.199.105:2380"
            ]
        }
    ]
}

Docker

You can use the following command to build a PD image directly:

docker build -t pingcap/pd .

Or you can also use following command to get PD from Docker hub:

docker pull pingcap/pd

Run a single node with Docker:

# Set correct HostIP here. 
export HostIP="192.168.199.105"

docker run -d -p 1234:1234 -p 9090:9090 -p 2379:2379 -p 2380:2380 --name pd pingcap/pd \
          --cluster-id=1 \
          --host=${HostIP} \
          --name="pd" \
          --initial-cluster="pd=http://${HostIP}:2380" 

Cluster

For how to set up and use PD cluster, see clustering.