Using the Cluster Tab

Use the Clusters tab to create, monitor and manage active clusters.

The clusters tab

The Clusters tab.

Indicators in the columns to the right of a cluster name display the current health of the cluster. Click on a column name to sort the contents of the column; click a second time to reverse the sort-order.

  • The VM column displays the state of the virtual machine on which the cluster resides.
  • The HA column displays the state of the high-availability cluster.
  • The DB column displays the state of the database server.
  • The UP column displays the current status of the packages installed on the cluster. Periodically, the cluster manager performs a check to see if the packages are up to date.

Status indicators provide quick visual feedback about each feature:

icon1 A green checkmark indicates that an object is healthy.
icon2 A yellow alert symbol calls attention to an object that requires attention.
icon3 A red error symbol signifies that an object is not available.
icon4 A busy-indicator signals that the cluster is processing a request.
icon5 A question mark indicates that the state of the resource is unknown.

To download an archive of log files, right-click on a node name and select:

  • Download DB Logs to download database server logs.
  • Download pgPool Logs to download pgPool (load balancing) logs.
Downloading log files

Downloading log files.

The menu options are context sensitive, displaying log types only for software that is deployed on the selected node. The archive name is in the following form:

<address>-<log_type>-<date>.tar.gz

Where:

address is the address of the selected node.

log_type is the type of log file (server type or pgPool).

date is the date that the archive was generated.

Archive preparation can take some time if your log files are large; the download will begin when the preparation completes.

Use the icons along the left side of the Clusters tab to create new clusters or manage existing clusters:

icon6 Use the New Cluster icon to create a new Postgres cluster.
icon7 Select the Scale Up icon to manually add one or more replicas to the current cluster, or add additional storage to the current cluster servers.
icon8 Use the Scale Down icon to remove one or more specified replicas from the cluster.
icon9 Select the Backup icon to take a backup of the highlighted cluster (a single backup of the cluster data, and a backup of the cluster configuration files).
icon10 Select the Clone icon to copy the master node of the selected database into a clone of the original master node. When you clone a database, only the master node is recreated in the new cluster.
icon11 You can use the Upgrade icon to open a dialog that allows you to perform a yum update (keeping the same server version) or perform an upgrade to a later server version. After performing an update, the cluster nodes will be rebooted (initiating any kernel updates required). Please note that a software update can take some time to complete.
icon12 Use the Scale Machine Type icon to change the size of the virtual machine for the selected cluster. CDS will copy the cluster into a new cluster of a different server class (i.e. RAM and CPU), and optionally re-assign the IP address of the existing cluster to the new cluster.
icon13 Use the Restart/Reload DB Servers icon to access a dialog that allows you to manage server operations.
icon14 Use the Administrative Settings icon to access a popup dialog that allows you to view or modify the ownership and notification email address of the currently selected cluster.
icon15 Use the Delete Cluster icon to delete the currently selected cluster. A popup dialog will ask you to confirm your decision to terminate a cluster; once terminated, a cluster may only be restored from a backup.

By default, the box next to Release elastic IP address is checked. Deselect this option if you wish to retain the IP address for re-use with other clusters. If you release the IP address, it will be made available for use by other clusters.

When you terminate an active cluster, backups are not deleted. Backups (including user data) are retained until they are selected and deleted from the Backups tab.

The panels located at the bottom of the Clusters tab provide easy access to helpful statistical usage and activity information about the currently selected cluster. Three navigation bars control the display; click a bar to access one of the following panels:

  • Open the Details panel to view information about the selected cluster.
  • Open the Monitoring panel to view usage statistics for the selected cluster.
  • Open the Events panel to review event logs describing activities on the selected cluster.

The Details Panel

Click the Details navigation bar to open the Details panel.

The details panel

The Details panel on the Clusters tab.

The left pane of the Details panel displays information about the currently selected cluster:

  • The name of the cluster
  • The date and time that the cluster was created
  • The name of the database superuser
  • The name of the cluster owner
  • The email address to which notifications about the cluster will be sent
  • The cluster size
  • If the cluster is encrypted
  • If applicable, the IOPS value for the cluster
  • The region in which the cluster resides
  • The virtual network or VPC ID in which the cluster resides
  • The cluster’s hardware type or Server Class
  • The engine type and version that resides on the server
  • If a template was used when provisioning the cluster, the template name
  • If the cluster is configured to update when provisioned

You can use controls on the Details panel to specify:

  • Failover preferences for the cluster
  • Auto-scaling thresholds for the cluster
  • Backup preferences for the cluster
  • If continuous archiving should be enabled for the cluster

Please note: If a template was used to specify the configuration details for the cluster, the template may prohibit access to auto-scaling or manual scaling functionality.

Selecting a Cluster Healing Mode

Use the Cluster healing mode radio buttons to specify the type of failover that should be employed:

  • Select the Replace failed master with a new master radio button to specify that the cluster manager should create a new master to replace a failed master node.

    When replacing a failed master node with a new master node, the data volumes from the failed instance are attached to the new master node, preserving data integrity, while the replicas continue serving client queries.

  • Select the Replace failed master with existing replica radio button to specify that the cluster manager should promote a replica node to be the new master node for the cluster.

    When replacing a failed master node with an existing replica, a replica node is marked for promotion to master node, while the other replica nodes are re-configured to replicate data from the new master node. Since replica nodes use asynchronous replication, any data that was committed to the old master node, but not pushed to the replica prior to the node failure will be lost.

Please note that replacing a failed master node with a new master node can take a bit longer than promoting a replica node to the role of master, but it does have the advantage of guaranteeing that no committed data will be lost. If recovery time for your cluster is more important than preserving any non-replicated transactions, then select Replace failed master with existing replica as the healing mode.

Adjusting Auto-Scaling Thresholds

Use the Auto-Scaling Thresholds controls on the Details panel to adjust the threshold at which CDS automatically scales up cluster resources. When auto-scaling in enabled, CDS monitors the server storage and connection resources in use, and automatically adds additional resources when usage exceeds a user specified percent.

  • When the % of Storage Size used is reached, CDS will automatically increase your data space by 50%.
  • When the # of Server Connections is reached, CDS adds replica nodes.

Use the Auto Scale Options controls to adjust the threshold at which CDS automatically scales up cluster resources. The Auto Scale Options controls are located on the Details panel; to access the Details panel, navigate to the Clusters tab, and highlight the name of a cluster.

Automatic scaling options

Auto Scale Options controls.

Adjust the Auto Scale Options sliders to increase or decrease the thresholds at which automatic scaling is invoked. When you modify the values, CDS will display a New Value Saved notice, alerting you that your changes have been saved.

Modifying Backup Settings

Use the fields in the Backup Settings box to change your backup preferences for the selected cluster:

  • Use the Backup Window drop-down listbox to select an optimal time to process cluster backups; specify a time when the number of clients accessing the database is minimal.

  • Use the Backup Retention field to specify the number of backups that should be stored for the selected cluster.

  • Select the checkbox next to Continuous Archiving (Point-in-Time Recovery) to enable point-in-time recovery for a cluster. When enabled, a base backup is automatically performed that can to be used to restore to a specific point in time. All subsequent automatic scheduled backups will also support point-in-time recovery. Note that if you deselect this option, the cluster (and subsequent automatic backups) will be re-configured to not include support for point-in-time recovery.

    When point-in-time recovery is enabled, the value specified in the Backup Retention field determines the duration of the point-in-time recovery backup window. For example, if you specify a value of 7, the backup window will be 7 calendar days long. When the backup retention threshold is reached, the oldest base backup is removed, as well as any WAL files required to perform a recovery with that backup.

Reviewing Cluster Connection and Status Information

The right side of the Details panel contains a status overview and connection information for the selected cluster. If you have created replicas, the secondary server nodes are listed below the master node in the tree control; expand the tree control to view the status of the replication nodes.

Status indicators on the Clusters tab provide quick visual feedback about the status of your cluster:

  • A green checkmark indicates that an object is healthy.
  • A yellow alert symbol calls attention to an object that requires attention.
  • A red error symbol signifies that an object is not available.
  • A question mark indicates that the state of the resource is unknown.

On the Details panel, use the settings icon in the upper-right corner of the `UP column to open a tab that allows you to select the columns that will be displayed in the panel.

The column selection tab

The column selection tab.

The columns display:

  • The AZ column displays the Availability Zone in which the cluster resides.
  • The VPC ID column displays the identifier of the VPC on which the cluster resides.
  • The LBPORT column displays the port number to which a client application should connect to utilize load balancing.
  • The DBPORT column displays the default listener port for the Advanced Server or PostgreSQL server.
  • The CXN column displays the current number of connections to the node.
  • The VM column displays the state of the virtual machine on which the cluster resides.
  • The HA column displays the state of the high-availability cluster.
  • The DB column displays the state of the database server.
  • The UP column displays the current status of the packages installed on the cluster. Periodically, the cluster manager performs a check to see if the packages are up to date. If an update becomes available, the UP column will display a yellow alert symbol (if the update is non-critical), or a red error symbol (if the update is a critical security alert).

The Monitoring Panel

Click the Monitoring navigation bar to open the Monitoring panel.

The Monitoring panel displays graphs that allow you to review statistical usage information about the amount of storage and the CPU load for the selected cluster.

The monitoring panel

The Monitoring panel displays usage information.

Use the Time Range drop-down listbox to modify the time period that the charted information on the Monitoring panel spans.

The graphs on the Monitoring panel display resource usage information:

  • The Data Space chart displays the amount of allocated data space used by the selected cluster. The red line denotes the threshold specified by the Data Space Threshold slider on the Details panel (the threshold at which the cluster will be scaled-up). The blue line indicates the amount of the data space that is currently in use.
  • The Connections chart displays a graph of the number of connections to the cluster during the selected time range. The red line denotes the threshold specified by the Connections slider on the Details panel.
  • The Load chart displays the processing load placed on the CPU by connecting clients. The value displayed is the actual load average as read from the program, /proc/loadavg. The chart shows the number of jobs in the run queue or waiting for disk I/O, averaged over 15 minute periods.
  • The Replication Lag chart displays the replication lag (in seconds) for the cluster. Each replica node is displayed as a separate colored line on the chart; the key at the bottom of the chart identifies the IP address of the node.

The Events Panel

Click the Events navigation bar to open the Events panel.

The Events panel displays an event log containing a history of selected events for the connected user.

The events panel

The Events panel displays server activity.

Highlight a cluster name to display only events for that cluster; if you do not select a cluster, the Events panel will display the collected events for the connected user.

  • Click a column heading to sort the logged activity by the selected column; click again to reverse the sort order.
  • Use the mouse to select multiple rows from the event log for copy and paste operations.