The F5 Server Layer
Every physical server in a server pool is mapped by the BIG-IP load balancer to one or more virtual servers. A Virtual Server is a combination of virtual address and virtual port, associated with a content site that is managed by a BIG-IP system. When the load balancer receives requests from clients to a virtual server, it routes them to the appropriate physical server in the pool.
The F5Status test associated with this layer reports the status of incoming and outgoing traffic through a load balancer (see Figure 1).