After all the servers that will be apart of the cluster have been added to the load balancer's vLAN the first step in using the load balancer is to create a service add servers to it and then configure the service.
Please note, only the servers in the cluster that will receive connections directly from the load balancer need to be added into the load balancer cluster.
In the following example cluster:
Only the web servers need adding into the load balancer service. This is because they will receive all of the incoming requests from the load balancer. The DB server will only receive data from the web servers. The DB server must, however, be added to the load balancer vLAN to enable rapid communication with the web servers.
A service is the name given to a named, discreet load balancer configuration based on a protocol and a port. An example would be a website cluster that uses the load balancer to distribute the incoming HTTP page requests to s server cluster. This service would be configured to listen externally (i.e. the public, internet facing side of the load balancer) on port 80 and then redirect those requests to the waiting web servers on the internal, vLAN side which are also listening on port 80. It has a single public IP address and appears to the internet as a single server.
A service is created and configured via the Service Manager link which can be found via the manage link to the right of each load balancer on load balancer summary page.
The Service Manager page is where new load balancer services are created and configured.
If no services have been created then this link will go directly to the form to create a new service. The following is an example of the form with the parts labelled and explained:
In order to create a service all parts of the form must be configured. These parts numbered above are as follows:
Each service can only be configured to use a single protocol such as HTTP. If a second is needed for the same cluster, typically HTTP along side HTTPS, then a second service should be created using the same servers but the second protocol.
The service will be created when the Add button is clicked. Once a service is created the Service Manager link will show a list of all the created services. The above service example looks like the following after it has been created:
After it has been created and appears as an available service on the Service Manager page. The Manage link shown above in the actions column will take you to the configuration page.
The Manage page for the above service looks like the following, with the majour sections numbered for explanation:
This shows the service configuration page for the example web cluster shown above.
There are only two servers listed despite the cluster contain three servers (two web servers and a database server) because the load balancer will only communicate directly with the two web servers. The database servers needs to be on the vLAN in order that the web servers can communicate via LAN speeds.
Please note that the Update buttons on this page will only save the configuration, they will not put it live on the load balancer. In order to put the configuration live the Update Now button that will appear when there is saved but not live new configuration on the first Service Manager page.
The service configuration page is split into three sections which are explained below:
Last updated 11 February 2016, 10:14 GMT