MariaDB Enterprise ColumnStore Removing a Node

Overview

To remove a node from Enterprise ColumnStore, perform the following procedure.

Check the Service in MaxScale

To confirm that the server object was properly unlinked from the service, the service should be checked using MaxScale's REST API:

For example:

$ maxctrl show services

Check the Monitor in MaxScale

To confirm that the server object was properly unlinked from the monitor, the monitor should be checked using MaxScale's REST API:

For example:

$ maxctrl show monitors

Remove the Server from MaxScale

The server object for the node must also be removed from MaxScale using MaxScale's REST API:

  • Use MaxCtrl or another supported REST client

  • Remove the server object using the destroy server command

  • As the first argument, provide the name for the server

For example:

$ maxctrl destroy server \
   mcs3

Check the Server in MaxScale

To confirm that the server object was properly removed, the server objects should be checked using MaxScale's REST API:

For example:

$ maxctrl show servers

Stop the Enterprise ColumnStore Services

The Enterprise Server. Enterprise ColumnStore, and CMAPI services can be stopped using the systemctl command.

Perform the following procedure on the node:

  1. Stop the MariaDB Enterprise Server service:

    $ sudo systemctl stop mariadb
    
  2. Stop the MariaDB Enterprise ColumnStore service:

    $ sudo systemctl stop mariadb-columnstore
    
  3. Stop the CMAPI service:

    $ sudo systemctl stop mariadb-columnstore-cmapi
    

Remove the Node from Enterprise ColumnStore

The node must be removed from Enterprise ColumnStore using CMAPI:

For example, if the primary node's host name is mcs1 and the IP address for the node to remove is 192.0.2.3:

  • In ES 10.5.10-7 and later:

    $ curl -k -s -X DELETE https://mcs1:8640/cmapi/0.4.0/cluster/node \
       --header 'Content-Type:application/json' \
       --header 'x-api-key:93816fa66cc2d8c224e62275bd4f248234dd4947b68d4af2b29671dd7d5532dd' \
       --data '{"timeout":20, "node": "192.0.2.3"}' \
       | jq .
    
  • In ES 10.5.9-6 and earlier:

    $ curl -k -s -X PUT https://mcs1:8640/cmapi/0.4.0/cluster/remove-node \
       --header 'Content-Type:application/json' \
       --header 'x-api-key:93816fa66cc2d8c224e62275bd4f248234dd4947b68d4af2b29671dd7d5532dd' \
       --data '{"timeout":20, "node": "192.0.2.3"}' \
       | jq .
    

Example output:

{
  "timestamp": "2020-10-28 00:39:14.672142",
  "node_id": "192.0.2.3"
}

Check Enterprise ColumnStore Status

To confirm that the node was properly removed, the status of Enterprise ColumnStore should be checked using CMAPI:

  • Check the status using the status endpoint path

For example, if the primary node's host name is mcs1:

$ curl -k -s https://mcs1:8640/cmapi/0.4.0/cluster/status \
   --header 'Content-Type:application/json' \
   --header 'x-api-key:93816fa66cc2d8c224e62275bd4f248234dd4947b68d4af2b29671dd7d5532dd' \
   | jq .

Example output:

{
  "timestamp": "2020-12-15 00:40:34.353574",
  "192.0.2.1": {
    "timestamp": "2020-12-15 00:40:34.362374",
    "uptime": 11467,
    "dbrm_mode": "master",
    "cluster_mode": "readwrite",
    "dbroots": [
      "1"
    ],
    "module_id": 1,
    "services": [
      {
        "name": "workernode",
        "pid": 19202
      },
      {
        "name": "controllernode",
        "pid": 19232
      },
      {
        "name": "PrimProc",
        "pid": 19254
      },
      {
        "name": "ExeMgr",
        "pid": 19292
      },
      {
        "name": "WriteEngine",
        "pid": 19316
      },
      {
        "name": "DMLProc",
        "pid": 19332
      },
      {
        "name": "DDLProc",
        "pid": 19366
      }
    ]
  },
  "192.0.2.2": {
    "timestamp": "2020-12-15 00:40:34.428554",
    "uptime": 11437,
    "dbrm_mode": "slave",
    "cluster_mode": "readonly",
    "dbroots": [
      "2"
    ],
    "module_id": 2,
    "services": [
      {
        "name": "workernode",
        "pid": 17789
      },
      {
        "name": "PrimProc",
        "pid": 17813
      },
      {
        "name": "ExeMgr",
        "pid": 17854
      },
      {
        "name": "WriteEngine",
        "pid": 17877
      }
    ]
  },
  "num_nodes": 2
}