ClusterControl Documentation
Use the menu below or the search below to learn everything you need to know about ClusterControl


This page is the landing page once you are logged in. It provides a summary of database clusters monitored by ClusterControl.


Top Menu

ClusterControl’s top menu.


Left-side navigation provides quick access to ClusterControl administration menu. See Sidebar.

Cluster List

List of database clusters managed by ClusterControl with summarized status. Database cluster deployed by (or imported into) ClusterControl will be listed in this page. See Database Cluster List.

Cluster Actions

Provides shortcuts to main cluster functionality. Every supported database cluster has its own set of menu:


Clicking on it will expand the activity tab which consists of Alarms, Jobs and Logs. Click once more to collapse the content. If you rolled over the menu icon, you would see a counter summary for every component.


Shows aggregated view of alarms raised for all clusters monitored by ClusterControl. Each alarm entry has a header, details on the issue, severity level, category, corresponding cluster name, corresponding host and timestamp. All the alarms listed here are also accessible directly under individual cluster main menu available at Alarms > Alarms.

Click on the alarm entry itself to see the full details and recommendation. Furthermore, you can click on the “Full Alarm Details” to see the full information, recommendation and to send out this alarm as an email to the recipients configured under Settings > CMON Settings > Email Notification Settings. Click “Ignore Alarm” to silent the respective alarm from appearing in the list again.


Shows aggregated view of jobs that have been initiated and performed by ClusterControl across clusters (e.g., deploying a new cluster, adding an existing cluster, cloning, creating backup, etc). Each job entry has a job status, a cluster name, which user started the job and also timestamp. All the jobs listed here are also accessible directly under individual cluster main menu available at Logs > Jobs.

Click on the job entry itself to see its most recent job messages. Furthermore, you can click on the Full Job Details to see the full job specification and messages. Under the Full Job Details popup, you have the ability to see the full command sent to the controller service for that particular job by clicking on Expand Job Specs button. Underneath it is the full job messages in descending order (newer first) returned by the controller service. Copy to clipboard button will copy the content of the job messages to the clipboard.


Starting from v1.6, ClusterControl has a better support for parallelism, where you can perform multiple deployments simultaneously.

The job status:

Job status Description
FINISHED The job is successfully executed.
FAILED The job is executed but failed.
RUNNING The job is started and in progress.
ABORTED The job is started but terminated.
DEFINED The job is defined but yet to start.


Shows aggregated view of ClusterControl logs which require user’s attention across clusters (logs with severity WARNING and ERROR). Each log entry has a message subject, severity level, component, the corresponding cluster name and also timestamp. All the logs listed here are also accessible directly under individual cluster at Logs > CMON Logs.

Global Settings

Provides interface to register clusters, repositories and subscriptions inside ClusterControl.


Manages provider’s repository for database servers and clusters. You can have three types of repository when deploying database server/cluster using ClusterControl:

  1. Use Vendor Repositories
    • Provision software by setting up and using the database vendor’s preferred software repository. ClusterControl will always install the latest version of what is provided by database vendor repository.
  2. Do Not Setup Vendor Repositories
    • Provision software by using the pre-existing software repository already setup on the nodes. User has to set up the software repository manually on each database node and ClusterControl will use this repository for deployment. This is good if the database nodes are running without internet connections.
  3. Use Mirrored Repositories (Create new repository)
    • Create and mirror the current database vendor’s repository and then deploy using the local mirrored repository.
    • This allows you to “freeze” the current versions of the software packages used to provision a database cluster for a specific vendor and you can later use that mirrored repository to provision the same set of versions when adding more nodes or deploying other clusters.
    • ClusterControl sets up the mirrored repository under {wwwroot}/cmon-repos/, which is accessible via HTTP at http://ClusterControl_host/cmon-repos/.

Only Local Mirrored Repository will be listed and manageable here.

  • Remove Repositories
    • Remove the selected repository.
  • Filter by cluster type
    • Filter the repository list by cluster type.

For reference purpose, following is an example of yum definition if Local Mirrored Repository is configured on the database nodes:

$ cat /etc/yum.repos.d/clustercontrol-percona-5.6-yum-el7.repo
name = percona-5.6-yum-el7
baseurl =
enabled = 1
gpgcheck = 0
gpgkey =

Cluster Registrations

Registers a database cluster managed by ClusterControl Controller (CMON) to be viewed by ClusterControl UI. Each database cluster can be registered with the UI through this interface or you may skip doing this and use ClusterControl CLI instead. By default, all clusters deployed by and imported into ClusterControl through the web interface will be automatically registered with the UI. This effectively establishes the communication between the UI and the controller.



ClusterControl introduces new license format on v1.7.1 (the new license key format contains only a long-encrypted string). If you are having the older format, contact the account manager or email our sales department at to get a new license.

For users with a valid subscription (Advanced and Enterprise), enter your license key here to unlock additional features based on the subscription. The license string contains information about the license type, company/affilication, email, expiration date and total number of licensed nodes.

The following example is the license information that one would get from us:

Company: Severalnines AB
Expiration Date: 2019-04-23
Licensed Nodes: 1
License Key: ewogICAgImNvbXBhbnkiOiAiU2V2ZXJhbG5pbmPkIEFCIiwKICAgICJlbWFpbF9hZGRyZXNzIjog

Only paste the license key string (starting after “License Key: ” part) into the license text field. Once applied, restart CMON service to load the new license information:

$ systemctl restart cmon # systemd
$ service cmon restart # SysVinit

When the license expires, ClusterControl defaults back to the Community Edition. For features comparison, please refer to ClusterControl product page.

If you would like to force the existing enteprise edition to community edition (commonly to test out and compare different editions during trial), you can truncate the license table on the ClusterControl host manually. On ClusterControl server, run:

$ mysql -uroot -p cmon
mysql> truncate table cmon.license
$ systemctl restart cmon


Once a trial license is truncated and cmon is restarted, there is no way you can re-activate a trial licence anymore. Only a working enterprise license will be working as trial license can’t be applied more than once.

Configure Mail Server

Configures how email notifications should be sent out. ClusterControl supports two options for sending email notifications, either using local mail commands via local MTA (Sendmail/Postfix/Exim) or using an external SMTP server. Make sure the local MTA is installed and verified using Test Email button.

Use Sendmail

  • Use sendmail
    • Use this option to use sendmail to send notifications. See Installing Sendmail if you haven’t installed Sendmail. If you want to use Postfix, see Using Postfix.
  • Reply-to/From
    • Specify the sender of the email. This will appear in the ‘From’ field of mail header.
Installing Sendmail

On ClusterControl server, install the following packages:

$ apt-get install sendmail mailutils #Debian/Ubuntu
$ yum install sendmail mailx #RHEL/CentOS

Start the sendmail service:

$ systemctl start sendmail #systemd
$ service sendmail start #sysvinit

Verify if it works:

$ echo "test message" | mail -s "test subject" [email protected]

Replace with your email address.

Using Postfix

Many of Linux distributions come with Sendmail as default MTA. To replace Sendmail and use other MTA, e.g Postfix, you just need to uninstall Sendmail, install Postfix and start the service. Following example shows commands that need to be executed on ClusterControl node as root user for RHEL:

$ service sendmail stop
$ yum remove sendmail -y
$ yum install postfix mailx cronie -y
$ chkconfig postfix on
$ service postfix start

Runtime Configurations

A shortcut to ClusterControl Controller runtime configurations per cluster. Runtime configuration shows the active ClusterControl Controller (CMON) runtime configuration parameters and displays the versions of ClusterControl Controller and ClusterControl UI packages. All parameters listed are loaded directly from cmon.cmon_configuration table, grouped by cluster ID.

Clicking on any of the list will redirect user to the Runtime Configurations page for that particular cluster.

Database Cluster List

Each row represents the summarized status of a database cluster:

Field Description
Cluster Name The cluster name, configured under ClusterControl > Settings > CMON Settings > General Settings > Name.
ID The cluster identifier number.
Version Database server major version.
Database Vendor Database vendor icon.
Cluster Type

The database cluster type:

  • MYSQL_SERVER - Standalone MySQL server.
  • REPLICATION - MySQL/MariaDB Replication.
  • GALERA - MySQL Galera Cluster, Percona XtraDB Cluster, MariaDB Galera Cluster.
  • GROUP_REPLICATION - MySQL Group Replication.
  • MONGODB - MongoDB ReplicaSet, MongoDB Sharded Cluster, MongoDB Replicated Sharded Cluster.
  • POSTGRESQL - PostgreSQL Standalone or Replication.
Cluster Status

The cluster status:

  • ACTIVE (green) - The cluster is up and running. All cluster nodes are running normally.
  • DEGRADED (yellow) - The full set of nodes in a cluster is not available. One or more nodes is down or unreachable.
  • FAILURE (red) - The cluster is down. Probably that all or most of the nodes are down or unreachable, resulting the cluster fails to operate as expected.
Auto Recovery

The auto recovery status of Galera Cluster:

  • Cluster - If sets to ON, ClusterControl will perform automatic recovery if it detects cluster failure.
  • Node - If sets to ON, ClusterControl will perform automatic recovery if it detects node failure.
Node Type and Status See table on node status indicators below.

Node status indicator:

Indicator Description
Green (tick) OK: Indicates the node is working fine.
Yellow (exclamation) WARNING: Indicates the node is degraded and not fully performing as expected.
Red (wrench) MAINTENANCE: Indicates that maintenance mode is on for this node.
Dark red (cross) PROBLEMATIC: Indicates the node is down or unreachable.