ClusterControl Documentation
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5.5.11. Settings

Settings for the cluster including general settings, mail notifications and thresholds.

5.5.11.1. CMON Settings

5.5.11.1.1. General Settings

  • Cluster Name
    • Cluster name. This name will appear in the database cluster list and database cluster summary.
  • Staging Area
    • The staging area is a directory (created automatically) to store intermediate data, such as dump files, binaries, packages used in installations, upgrades or scaling. The staging area is automatically cleaned, but should be big enough to hold dump files of your entire database.
  • Sudo
    • Sudo command password (if SSH User* is not root) if running as sudoers. Change in CMON configuration file under sudo.
  • SSH User
    • Read-only. The user that can SSH from the ClusterControl Server to the other nodes without password. Change in CMON configuration file under os_user or osuser.
  • SSH Identity
    • Read-only. Change in CMON configuration file under ssh_identity.
  • History
    • Number of days you would like to keep historic data. Ensure you have enough disk space on the ClusterControl server if you want to store historic data.
  • Log Interval
    • How many minutes between automatic PostgreSQL main log retrieval.

5.5.11.1.2. Configure Mailserver

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.

5.5.11.1.2.1. Option 1: Sendmail

  • Use sendmail
  • Reply-to/From
    • Specify the sender of the email. This will appear in the ‘From’ field of mail header.

5.5.11.1.2.3. 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

5.5.11.1.3. Email Notification Settings

Configures email notification settings for alarms generated for the cluster.

  • Send email to
    • Recipient email address.
  • Send digests at
    • Send a digested (summary) email at this time every dayf or the selected recipient.
  • Timezone
    • Timezone for the selected recipient.
  • Daily limit for non-digest email as
    • The maximum number of non-digest email notification should be sent per day for the selected recipient. -1 for unlimited.
  • Alarm/Event Category
    Event Description
    Network Network related messages, e.g host unreachable, SSH issues.
    CmonDatabase Internal CMON database related messages.
    Mail Mail system related messages.
    Cluster Cluster related messages, e.g cluster failed.
    ClusterConfiguration Cluster configuration messages, e.g software configuration messages.
    ClusterRecovery Recovery messages like cluster or node recovery failures.
    Node Message related to nodes, e.g node disconnected, failed to start PostgreSQL nodes.
    Host Host related messages, e.g CPU/disk/RAM/swap alarms.
    DbHealth Database health related messages, e.g memory usage of mysql servers, connections.
    DbPerformance Alarms for long running transactions and deadlocks
    SoftwareInstallation Software installation related messages.
    Backup Messages about backups.
    Unknown Other uncategorized messages.
  • Select how you wants alarms/events delivered
    Action Description
    Ignore Ignore if an alarm raised.
    Deliver Send notification immediately via email once an alarm raised.
    Digest Send a summary of alarms raised everyday at Send digests at

5.5.11.2. Runtime Configuration

Summarizes the active ClusterControl Controller (CMON) runtime configuration parameters and displays the versions of ClusterControl Controller and ClusterControl UI packages. All parameters listed here are loaded directly from cmon.cmon_configuration table, displayed by the current cluster ID. You can filter out the variables by using the Search field on top of the table. Each parameter has the Current Value (the active value loaded into ClusterControl) and also the Default Value (if undefined, ClusterControl will use this value) as well as description of the parameter.

Some configuration parameters can be modified directly from the UI like swap_warning (Settings > Thresholds > Swap Warning) and backup_subdir (Backup > Settings > Default Backup Subdirectory). Some parameters have to be set inside CMON configuration file for the respective cluster ID.

Thus, there are two ways to modify the value of any parameter:

  1. Change the value directly from the UI if exists. This will save it into cmon database. No cmon restart requires.
  2. Append the parameter line inside CMON configuration file for the respective cluster at /etc/cmon.d/cmon_X.cnf (where X is the cluster ID). This requires cmon restart to get it loaded into cmon database.

As a side note, the settings that are set through UI will always take precedence.

Note

You can also run cmon --help-config to get the details of supported parameters.

5.5.11.3. Thresholds

Provides thresholds for warnings and criticals event. Thresholds specify the threshold level at which an alarm will be triggered and notification will be sent via email to the list of recipients configured in the Email Notification Settings. Set your alarm thresholds for:

  • CPU utilization
  • RAM utilization
  • Disk space utilization
  • Swap space
Level Description
Warning Sets your warning threshold in percentage for specific event.
Critical Sets your critical threshold in percentage for specific event.