ClusterControl Docker Image

Supported Tags
Overview
Image Description
Run Container
Environment Variables
Service Management
Examples
Development
Disclaimer

Supported Tags

Overview

ClusterControl is a management and automation software for database clusters. It helps deploy, monitor, manage and scale your database cluster. This Docker image comes with ClusterControl installed and configured with all of its components so you can immediately use it to deploy new set of database servers/clusters or manage existing database servers/clusters.

Supported database servers/clusters:

Percona XtraDB Cluster
MariaDB Galera Cluster
MySQL/MariaDB (standalone & replication)
MySQL Cluster (NDB)
MongoDB (replica set & sharded cluster)
PostgreSQL (standalone & streaming replication)
TimescaleDB (standalone & streaming replication)
Redis (replication & Sentinel) - via ClusterControl GUI v2
SQL Server 2019 for Linux (standalone & Availability Group) - via ClusterControl GUI v2
Elasticsearch - via ClusterControl GUI v2

More details at Severalnines website.

Image Description

To pull ClusterControl images, simply:

$ docker pull severalnines/clustercontrol

The image is based on CentOS 7 with Apache 2.4, which consists of ClusterControl packages and prerequisite components:

ClusterControl controller, GUI v1, GUI v2, cloud, notification and web-ssh packages installed via Severalnines repository.
MySQL, CMON database, cmon user grant and dcps database for ClusterControl UI.
Apache, file and directory permission for ClusterControl UI with SSL installed.
SSH key for ClusterControl usage.

Run Container

To run a ClusterControl container, the simplest command would be:

$ docker run -d severalnines/clustercontrol

However, for production use, users are advised to run with sticky IP address/hostname and persistent volumes to survive across restarts, upgrades and rescheduling, as shown below:

# Create a Docker network
$ docker network create --subnet=192.168.10.0/24 db-cluster

# Start the container
$ docker run -d --name clustercontrol \
--network db-cluster \
--ip 192.168.10.10 \
-h clustercontrol \
-p 5000:80 \
-p 5001:443 \
-p 9443:9443 \
-p 19501:19501 \
-e DOCKER_HOST_ADDRESS=192.168.11.111 \
-v /storage/clustercontrol/cmon.d:/etc/cmon.d \
-v /storage/clustercontrol/datadir:/var/lib/mysql \
-v /storage/clustercontrol/sshkey:/root/.ssh \
-v /storage/clustercontrol/cmonlib:/var/lib/cmon \
-v /storage/clustercontrol/backups:/root/backups \
severalnines/clustercontrol

ATTENTION

Starting from ClusterControl 1.9.1 (Dec 2021), DOCKER_HOST_ADDRESS is mandatory for ClusterControl GUI v2 to run correctly. If the container is running on Docker bridge network, additional ports 9443 and 19501 must be published.

The recommended persistent volumes are:

/etc/cmon.d - ClusterControl configuration files.
/var/lib/mysql - MySQL datadir to host cmon and dcps database.
/root/.ssh - SSH private and public keys.
/var/lib/cmon - ClusterControl internal files.
/root/backups - Default backup directory only if ClusterControl is the backup destination

Alternatively, if you would like to enable agent-based monitoring via Prometheus, you have to make the following paths persistent as well:

/var/lib/prometheus - Prometheus data directory.
/etc/prometheus - Prometheus configuration directory.

Therefore, the run command for agent-based monitoring via Prometheus would be:

$ docker run -d --name clustercontrol \
--network db-cluster \
--ip 192.168.10.10 \
-h clustercontrol \
-p 5000:80 \
-p 5001:443 \
-p 9443:9443 \
-p 19501:19501 \
-e DOCKER_HOST_ADDRESS=192.168.11.111 \
-v /storage/clustercontrol/cmon.d:/etc/cmon.d \
-v /storage/clustercontrol/datadir:/var/lib/mysql \
-v /storage/clustercontrol/sshkey:/root/.ssh \
-v /storage/clustercontrol/cmonlib:/var/lib/cmon \
-v /storage/clustercontrol/backups:/root/backups \
-v /storage/clustercontrol/prom-data:/var/lib/prometheus \
-v /storage/clustercontrol/prom-conf:/etc/prometheus \
severalnines/clustercontrol

ATTENTION

After a moment, you should be able to access the following ClusterControl Web UIs:

ClusterControl GUI v1 HTTP: http://192.168.11.111:5000/clustercontrol
ClusterControl GUI v1 HTTPS: https://192.168.11.111:5001/clustercontrol
ClusterControl GUI v2 HTTPS: https://192.168.11.111:9443/

Environment Variables

DOCKER_HOST_ADDRESS={IP address or hostname} - This value should be the same as the Docker host primary IP address, or hostname/FQDN that resolves to the Docker host's primary IP address.
- Starting from ClusterControl 1.9.1, this environment variable is mandatory. If the container is running on Docker bridge network, additional ports 9443 and 19501 must be published.
  - Example: DOCKER_HOST_ADDRESS=192.168.11.111
CMON_PASSWORD={string}
- MySQL password for user 'cmon'. Default to 'cmon'. Use docker secret is recommended.
- Example: CMON_PASSWORD=cmonP4s5
MYSQL_ROOT_PASSWORD={string}
- MySQL root password for the ClusterControl container. Default to 'password'. Use docker secret is recommended.
- Example: MYSQL_ROOT_PASSWORD=MyPassW0rd
CMON_STOP_TIMEOUT={integer}
- How long to wait (in seconds) for CMON to gracefully stop (SIGTERM) during container bootstrapping process. Default is 30.
- If the timeout is exceeded, CMON will be stopped using SIGKILL.
- Example: CMON_STOP_TIMEOUT=15

Service Management

ClusterControl requires a number of processes to be running:

sshd - SSH daemon. The main communication channel.
mysqld - MySQL backend runs on Percona Server 5.6.
httpd - Web server running on Apache 2.4.
cmon - ClusterControl backend daemon. The brain of ClusterControl. It depends on mysqld and sshd.
cmon-ssh - ClusterControl web-based SSH daemon, which depends on cmon and httpd.
cmon-events - ClusterControl notifications daemon, which depends on cmon and httpd.
cmon-cloud - ClusterControl cloud integration daemon, which depends on cmon and httpd.
cc-auto-deployment - ClusterControl automatic deployment script, running as a background process, which depends on cmon.

These processes are being controlled by Supervisord, a process control system. To manage a process, one would use supervisorctl client as shown in the following example:

[root@physical-host]$ docker exec -it clustercontrol /bin/bash
[root@clustercontrol /]# supervisorctl
cc-auto-deployment               RUNNING   pid 570, uptime 2 days, 19:11:54
cmon                             RUNNING   pid 573, uptime 2 days, 19:11:54
cmon-events                      RUNNING   pid 576, uptime 2 days, 19:11:54
cmon-ssh                         RUNNING   pid 575, uptime 2 days, 19:11:54
httpd                            RUNNING   pid 571, uptime 2 days, 19:11:54
mysqld                           RUNNING   pid 577, uptime 2 days, 19:11:54
sshd                             RUNNING   pid 572, uptime 2 days, 19:11:54
supervisor> restart cmon
cmon: stopped
cmon: started
supervisor> status cmon
cmon                             RUNNING   pid 2838, uptime 0:11:12
supervisor>

In some cases, you might need to restart the related service after a manual upgrade or configuration tuning. Details on the start commands can be found inside conf/supervisord.conf.

Examples

Development

Please report bugs, improvements or suggestions via our support channel: https://support.severalnines.com

If you have any questions, you are welcome to get in touch via our contact us page or email us at info@severalnines.com.

Disclaimer

Although Severalnines offers ClusterCluster as a Docker image, it is not intended for production usage. ClusterControl product direction is never intended to run on a container environment due to its internal logic and system design. We are maintaining the Docker image on a best-effort basis, and it is not part of the product development projection and pipeline.

kunthar / cc-docker