5.5

Static Routes Between vApp Networks
For an example of a static routing service in a vApp network, see “Network Services in vApp Networks,” on
page 131.
Load Balancer Service Configurations
An Edge Gateway can provide load-balancing services that allow you to distribute incoming requests to a
specific external IP address across multiple internal IP addresses. Several load-balancing algorithms are
supported.
A load balancer service provides load balancing for TCP, HTTP, and HTTPS traffic. The load balancer
accepts incoming IP requests on an external or internal interface, and uses the algorithm you specify to
distribute requests across a pool of servers.
To add a load-balancer service to an Edge Gateway, include a LoadBalancerService element in the Edge
Gateway's EdgeGatewayServiceConfiguration.
Example: Load Balancer Service
This fragment of anEdgeGatewayServiceConfiguration defines a LoadBalancerService that accepts incoming
requests at external address https://192.168.1.100 and balances them across two servers at internal
addresses 10.200.100.10 and 10.200.100.11. The following elements define a LoadBalancerService:
n
A Pool that contains ServicePort and Member elements. A LoadBalancerService must include a Pool that
defines a ServicePort for each protocol on which the load balancer handles incoming requests. You can
define up to three ServicePort elements, one for each supported protocol (HTTP, HTTPS, TCP). This
load balancer handles only SSL (HTTPS) requests, so it requires only one ServicePort element in its
Pool.
You must specify one of the following load-balancing algorithms in the Algorithm element of the
ServicePort.
IP_HASH
Selects a server based on a hash of the source and destination IP address
of each packet.
LEAST_CONN
Distributes client requests to multiple servers based on the number of
connections already on the server. New connections are sent to the server
with the fewest connections.
ROUND_ROBIN
Each server is used in turn according to the weight assigned to it. This is
the smoothest and fairest algorithm when the server's processing time
remains equally distributed.
URI
The left part of the URI, before the question mark, is hashed and divided
by the total weight of the running servers. The result designates which
server receives the request, ensuring that a request is always directed to
the same server as long as all servers remain available.
The Pool in this example also defines an optional HealthCheck element that specifies parameters used
for periodic verification that all pool members are responding to requests.
Each Member element in the Pool specifies the IpAddress of a virtual machine that provides the service
being requested. Incoming requests are balanced across all members of the pool. Because the Algorithm
specified for this Pool is ROUND_ROBIN, each Member must be assigned a Weight.
vCloud API Programming Guide
184 VMware, Inc.