H3C Technologies H3C SecPath F1000-E - Manual (Page 875)

10
Configuration Considerations
Server load balancing
The server load balancing module comprises mainly a real service group, real services, and a virtual
service, as shown in Figure 12 .
Figure 12 Relationship between the components of the server load balancing module
Real service group
Real service 1 Real service 2 Real service n
Virtual service
......
• Real service group: A group of real services.
• Real services: Entities that process services in a cluster (such as servers in Figure 1 , and Figure 3 ,
and firewalls Figure 5 . A real service group corresponds to multiple real services.
• Virtual service: A logical entity that faces users. For server load balancing and firewall load
balancing, a virtual service corresponds to one real service group.
Server load balancing is implemented through the following procedure:
1. After a user sends a request to the virtual service of the LB device, if a persistence method is
specified in the virtual service, and matched persistence entries exist, the request is distributed
according to the persistence entries; otherwise, the virtual service obtains the information of the
related real service group, and then continues the following procedure. For introduction to
persistence method, see Table 5 .
2. If ACL is enabled for a virtual service, real services will be matched against ACL rules specified in
the real services one by one according to the weights of the real services. Requests allowed by the
ACL will be distributed to the corresponding real service; if requests are not allowed by the ACL or
no matched real services exist, the following procedure is continued.
3. Distributes the request to a real service in the group based on the algorithm configured in the real
service group.
Configuration Task List
NOTE:
To implement DR mode server load balancing , you must enable unidirectional traffic detection on the
page displayed by selecting Firewall > Session Table > Configuration on the LB device. For more
information, see
Session Management.
Perform the tasks in Table 1 to configure server load balancing.