Integrate F5 with contrail LBaaS APIs

Implement LBaaS in OpenContrail to support a physical/Virtual F5 loadbalancer.

F5 loadbalancer implements the abstract loadbalancer driver class, ContrailLoadBalancerAbstractDriver, provided by OpenContrail.

This driver is invoked from loadbalancer agent of SVC monitor and makes BIGIP interface call to configure the F5 device. All the configuration knobs to tune the driver is configured in Service Appliance Set object and passed to the driver by loadbalancer agent while loading the driver.

F5 Loadbalancer driver uses the BIGIP interface(V1.0.6) version. BIGIP interface is a python package extracted from loadbalancer plugin provided by F5. This low level driver uses either SOAP API or REST API.

In the first release of F5 loadbalancer agent, loadbalancer driver will be programmed in “global routed mode” using service appliance set property.

F5 Loadbalancer in global routed mode

In the Global routed mode all the VIPs are assumed to be routable from clients and all members are routable from F5 device. The entire configuration on F5 for L2 and L3 is assumed to be pre provisioned.

In the global routed mode, because all access to and from the F5 device is assumed to globally routed, there is no segregation between tenant services on F5 device possible. In other words, overlapping addresses across tenants/networks is not a valid configuration.

Following assumptions made for global routed mode of F5 LBaaS support

1. All tenant networks are in the same namespace as corporate network
2. IP Fabric is also in the same namespace as corporate network
3. All VIPs are also in the same namespace as tenant/corporate networks
4. F5 could be attached to corporate network or to IP Fabric