F5 Load Balancing
Cisco UCS Director supports the creation and monitoring of F5 load balancers.
Although load balancing may be prevalent in the routing environment, it is also of growing importance in the virtual networking and VM environment. Server load balancing is a mechanism for distributing traffic across multiple virtual servers, offering high application and server resource utilization.
Server load balancing (SLB) is the process of deciding to which server a load-balancing device should send a client request for service. For example, a client request can consist of an HTTP GET for a web page or an FTP GET to download a file. The job of the load balancer is to select the server that can successfully fulfill the client request and do so in the shortest amount of time without overloading either the server or the server farm as a whole.
Depending on the load-balancing algorithm or predictor that you configure, the F5 BIG-IP performs a series of checks and calculations to determine the server that can best service each client request. F5 BIG-IP bases server selection on several factors, including the server with the fewest connections regarding load, source or destination address, cookies, URLs, or HTTP headers.
A high-level process flow of load balancing is as follows:
-
A client attempts to connect with a service on the load balancer.
-
The load balancer accepts the connection.
-
The load balancer decides which host should receive the connection and changes the destination IP address (or port) in order to match the service of the selected host.
-
The host accepts the load balancer's connection and responds to the original source, to the client (through its default route), and to the load balancer.
-
The load balancer acquires the return packet from the host and changes the source IP address (or port) to correspond to the virtual server IP address and port, and forwards the packet back to the client.
-
The client receives the return packet, assuming it came from the virtual server, and continues the rest of the process.
Cisco UCS Director enables the management, orchestration, and monitoring of the F5 load balancer. Following is a summary of the crucial processes:
-
Add the F5 load balancer. To add the F5 load balancer, choose Physical Accounts page, click Managed Network Elements and then click Add Network Element.
. On the -
On adding the F5 load balancer as a managed element, Cisco UCS Director triggers Cisco UCS Director task inventory collection. The polling interval configured on the System Tasks specifies the frequency of inventory collection.
-
After the F5 load balancer is added to the Pod, it is listed with all other components of the pod environment at the account level. To see the F5 component information, choose Network page, choose the Pod and click Managed Network Elements.
. On the
There are two ways to implement load balancing on an F5 device using Cisco UCS Director:
-
Use an iApps (BIG-IP) application service.
iApps application templates let you configure the BIG-IP system for your HTTP applications, by functioning as an interface to consistently deploy, manage, and monitor your servers. You can use default iApps templates or create and customize a template to implement load balancing on the F5 device.
-
Use Cisco UCS Director to:
-
Set up a managed element
-
Create a Pool
-
Add pool members
-
Create a virtual server
-