Managing Serviceguard 11th Edition, Version A.11.16, Second Printing June 2004

Understanding Serviceguard Software Components
How the Network Manager Works
Chapter 3 105
this example, the aggregated ports are collectively known as lan900, the
name by which the aggregate is known on HP-UX 11i (on HP-UX 11.0,
the aggregates would begin with lan100).
Various combinations of Ethernet card types (single or dual-ported) and
aggregation groups are possible, but it is vitally important to remember
that at least two physical cards must be used in any combination of
APA’s to avoid a single point of failure for heartbeat connections.
HP-APA currently supports both automatic and manual configuration of
link aggregates.
For information about implementing APA with Serviceguard, see HP
Auto Port Aggregation (APA) Support Guide and other APA documents
posted at http://docs.hp.com in the Networking and Communications
collection.
VLAN Configurations
Virtual LAN configuration using HP-UX VLAN software is now
supported in Serviceguard clusters. VLAN is also supported on
dual-stack kernel.
What is VLAN?
Virtual LAN (or VLAN) is a networking technology that allows grouping
of network nodes based on an association rule regardless of their
physical locations. Specifically, VLAN can be used to divide a physical
LAN into multiple logical LAN segments or broadcast domains. Each
interface in a logical LAN will be assigned a tag id at the time it is
configured. VLAN interfaces, which share the same tag id, can
communicate to each other as if they were on the same physical network.
The advantages of creating virtual LANs are to reduce broadcast traffic,
increase network performance and security, and improve manageability.
On HP-UX, initial VLAN association rules are port-based, IP-based, and
protocol-based. Multiple VLAN interfaces can be configured from a
physical LAN interface and then appear to applications as regular
network interfaces. IP addresses can then be assigned on these VLAN
interfaces to form their own subnets. Please refer to the document Using
HP-UX VLAN (T1453-90001) for more details on how to configure VLAN
interfaces.