You can use an internal load balancer to optimize internal
communications between the Gateway servers and Management servers.
This is typically used when you want to gain finer control over load
distribution, particularly if your IBM® API
Connect cloud spans two
or more different geographical locations.
About this task
By default, gateway servers in a given cloud communicate
with all active Management servers in that cloud to receive configuration
updates and post analytics data. To optimize server communications,
you can choose to configure DNS and load balancing rules at each location
to resolve a single internal load balancing address only to the Management
servers that are in the same location. This configuration allows you
to obtain the best load distribution for your enterprise.
A
typical approach, for best performance, is to keep configuration and
analytics communications from Gateway servers to Management servers
within the same geographical location by preference, while still retaining
the ability to fail over to a different location.
Procedure
To configure IBM API
Connect to
use an internal load balancer, complete the following steps:
- Decide on a single common host name to be used for the
internal load balancer at each geographical location.
- At each location, configure DNS and load balancing rules
to resolve the internal load balancer host name to the Management
servers at that location. Configure the load balancing rules to forward
requests on ports 2443 and 9443, and to not terminate SSL connections
at the internal load balancer.
-
Ensure that the firewall is configured to allow communication from the Gateway servers to the
internal load balancer, and from the internal load balancer to the Management servers on the
required ports; for more information, see Firewall
requirements.
- Configure IBM API
Connect to
use the internal load balancer by completing the following steps:
- In the Cloud Manager, click Services.
-
In the Management Services pane, click the Service
Settings icon .
-
Select Use a different hostname for internal communication.
-
Enter the internal load balancer host name in the Hostname for internal communication field, and click Save Service.
The internal load balancer settings are propagated to each of the Gateway servers in the
API Connect cloud.
Note: It can take several minutes for the propagation of the settings to complete.
- Verify your internal load balancer configuration by completing
the following steps:
- In the Gateway Services pane, click the Server details icon for each Gateway server, and confirm that the managementLoadBalancingAddresses and analyticsLoadBalancingAddresses properties are set to the internal load balancer host name.
If you observe either of the
following conditions, it is likely that the internal load balancer
is incorrectly configured, or is not reachable:
- After a period of time, the managementLoadBalancingAddresses list indicates
softdown
status for the internal load balancer address.
- The analyticsLoadBalancingAddresses list contains the earlier addresses of each of the management servers in the cloud instead of the new internal load balancer address.
- Create, deploy, and publish a new API to each of the
gateway servers, and confirm that the following conditions are satisfied:
- You can successfully call the new API on each Gateway server.
- The new API calls are correctly reflected in the analytics information
displayed in the API Manager UI.