After you have configured both your vCenter Single Sign-On servers, you must configure your F5 BIG-IP load balancer, and remove the mappings to the load. This topic provides information for how to configure an F5 BIG-IP Local Traffic Manager (LTM) as a load balancer for Pivotal Application Service. Jump to Creating a Virtual Server - To get inventory information about the F5 device, navigate If you have created a virtual server for load balancing, you.
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Using WebLogic Server Clusters
Let's also assume that the ADC is already configured with a virtual f5 load balancer configuration that points to a cluster consisting of two service points. In this deployment scenario, it is common for the hosts to have a return route that points back to the load balancer so that return traffic will be processed through it on its way back to the client.
The basic application delivery transaction is as follows: The client attempts to connect with the service. The ADC accepts the connection, and after deciding which host should receive the connection, changes the destination IP and possibly port to match the service of the selected host note that the source IP of the client is not touched.
The host accepts the connection and responds back to the original source, the client, via its default route, the ADC. The ADC intercepts the return packet from the f5 load balancer configuration and now changes the source IP and possible port to match the virtual server IP and port, and forwards the packet back to the client.
Configure F5 BIG-IP as Load Balancer
The client receives f5 load balancer configuration return packet, believing that it came from the virtual server, and continues the process. A basic load balancing transaction. This very simple example is relatively straightforward, but there are a couple of key elements to note.
First, as far as the client knows, it sends packets to the virtual server and the virtual server responds—simple. Second, the NAT takes place. This is where the ADC replaces the destination IP sent by the client of the virtual server with the destination IP of the host to which it has chosen to load balance the request.
Third is the part of this process that makes the NAT "bi-directional". The source IP of the f5 load balancer configuration packet from the host will be the IP of the host; if this address f5 load balancer configuration not changed and the packet was simply forwarded to the client, the client would be receiving a packet from someone it didn't request one from, and would simply drop it.
Load Balancing Nuts and Bolts
Instead, the load balancer, f5 load balancer configuration the connection, rewrites the packet so that the source IP is that of the virtual server, thus solving this problem.
The application delivery decision Usually at this point, two questions arise: How does the load balancing ADC decide which host to send the connection to?
And what happens if the selected host isn't working?
Let's discuss the second question first. What happens if the selected host isn't working? The simple answer is that it doesn't respond f5 load balancer configuration the client request and the connection attempt eventually times out and fails.
This is obviously not a preferred circumstance, as it doesn't ensure high availability. That's why most load balancing technology includes some level of health monitoring to determine whether a host is actually available before attempting to send connections to it.
There are multiple levels of health monitoring, each with increasing granularity and focus. A basic monitor would simply ping the host itself. If the host does not respond to the ping, it is a good assumption f5 load balancer configuration any services defined on the host are probably down and should be removed from the cluster of available services.