3Com 3CR990SVR95, 3CR990-TX-97, 3CR990-TX-95, 3CR990SVR97 manual VLANs, Primary failure

3CR990 NIC Features 19

failed NIC. The failover behavior of secondary NICs depends on how you set load balancing:

■In a transmit load balancing arrangement, the primary NIC is the only one that receives packets. If the primary NIC fails, a secondary NIC assumes the configuration profile, network traffic, and active status of the failed primary NIC.

■In a bidirectional load balancing arrangement, all NICs receive packets. If any NIC fails, receive load balancing is disabled, and the other NICs continue transmit-only load balancing activity. Receive load balancing is restored when new connections are established with clients.

If any NIC in a bidirectional arrangement fails, receive load balancing is disabled, and the other NICs continue transmit-only load balancing activity. If the primary NIC fails, a secondary NIC takes over packet reception for the group.

Bidirectional load balancing is restored after a failure when applications create new connections and new clients log in.

Figure 3 Bidirectional Load Balancing Failover

Bidirectional	Primary failure	Secondary failure
load balancing

Server

Primary Secondaries Primary Secondaries Primary Secondaries

Switch

Clients

VLANs

A VLAN is a group of location-independent and topology-independent devices that communicate as if they were on the same physical LAN. Network devices on different LAN segments and of different media types can