Managing Availability groups - Platform - BlueCat Gateway - 23.1

Gateway Administration Guide
Locale
English
Product name
BlueCat Gateway
Version
23.1
You can do the following actions with an active Availability group within the Gateway UI:

 

Editing Availability group settings

When editing an existing Availability group, you can edit settings only for the Primary node. The Secondary node inherits settings from the Primary.

Tip: You can also configure most Availability settings for the Primary node before you add it to an Availability group. However, if you later add that instance as a Secondary node, those settings will be lost.
To edit the settings for an Availabilty group:

  1. From within the Gateway instance acting as a Primary node, open the Availability group settings (expand Configurations in the navigator on the left, then click Availability Group).

    Note: When editing an existing Availability group, you can edit settings only for the Primary node. The Secondary node inherits settings from the Primary.
    Tip: You can also configure most Availability settings for the Primary node before you add it to an Availability group. However, if you later add that instance as a Secondary node, those settings will be lost.

  2. In the lower left corner, click Edit configuration.

    The Edit Configuration window opens.

  3. Edit the Availability group settings as desired.
    Tip: For more details on what to enter for each field in the Availability group configuration screen, see Availability group Configuration settings.

    • In Primary IPv4 address, enter the IPv4 address for the primary Gateway node.

    • In the Availability group section, select the Scheme (http or https), and enter the FQDN (fully-qualified domain name), Port, and FQDN TTL (time to live).

      Make a note of what you select for these fields. Both nodes in an Availability group must have the same FQDN and port. Effectively, the FQDN identifies a specific Availability groups if you use multiple groups.

    • In the TSIG key section, enter the name of the TSIG key (transaction signature key), select an Algorithm, and enter the Secret Key.

      This TSIG key should be the same TSIG key you added to the Availability group's DNS zone for use by group.

    • (Optional) In the Failover settings section, edit the Failover settings for your Availability group.

      Note: We do not recommend changing these settings from their default values.

    When you're done, click Save to save your changes.

 

Removing the Secondary node from an Availability group

If you want to replace the current Secondary node with a different Gateway instance, you must first remove it from the group.

To remove the secondary Gateway instance from its Availability group:

  1. From within the Gateway instance acting as a Secondary node, open the Availability group settings (expand Configurations in the navigator on the left, then click Availability Group).

  2. In the lower right corner of the page, click Leave group.

    You will be asked to confirm the operation. Click Confirm.
    Note: Gateway on the Primary node will not be affected when you remove the Secondary node.
  3. You can now set up a different Gateway instance as the Secondary node.

 

Manually trigger a failover

You can manually trigger a failover within an active Availability group. Doing so forces the Secondary node to treat the Primary node as if it has failed.

To manually trigger an Availability group failover:

  1. From within the Gateway instance acting as the Secondary node, open the Availability group settings (expand Configurations in the navigator on the left, then click Availability Group).

  2. In the lower right corner of the page, click Failover. (If you don't see this button, then this instance is not the Secondary node for an Availability group.)

    You will be asked to confirm the operation. Click Confirm.

    The Secondary Gateway node will perform the standard failover process as if it detected that the Primary node had failed:
    • The node updates the DNS host record for the Availability group's fully-qualified domain name (FQDN) to point to itself (becoming the Primary).
    • The node updates the appropriate TXT records with a current timestamp, indicating that it is active and healthy.
    The node will now respond to all end user Gateway requests sent to that FQDN. Also, during its next heartbeat, the original Primary node checks the TXT records, discovers that it is no longer the Primary node, and assigns itself the role of Secondary node.

 

Disbanding an Availability group

When you disband an Availability group, all Availability group configuration settings are removed from the Gateway instances acting as the Primary and Secondary nodes. Neither will belong to any Availabilty group. Disbanding also removes the Availability group-related TXT records from the DNS server, used by an Availability group to track the health of the Primary node.

Note: The SOA record for the Availability group will not be deleted.

To disband an Availability group:

  1. From within the Gateway instance acting as the Primary node, open the Availability group settings (expand Configurations in the navigator on the left, then click Availability Group).

  2. In the lower right corner of the page, click Disband group. (If you don't see this button, then this instance is not the Primary node for an Availability group.)

    You will be asked to confirm the operation. Click Confirm.

    Gateway will remove both the Primary and Secondary nodes from the Availability group, also removing Availability-related TXT and HOST records from the DNS server.