1 Introduction
HP Auto Port Aggregation (APA) is a software product that creates link aggregates, often called
trunks, which provide a logical grouping of two or more physical ports into a single fat pipe.
This port arrangement provides more data bandwidth than would otherwise be available and
enables you to build large bandwidth logical links into the server that are highly available and
completely transparent to the client and server applications. HP APA provides the following
features:
•
Automatic link failure detection and recovery
•
Support for load balancing of network traffic across all of the links in the aggregation.
•
Support for the creation of failover groups, providing a failover capability for links. In the
event of a link failure, LAN Monitor automatically migrates traffic to a standby link.
•
Support for the TCP Segmentation Offload (Large Send) feature, if an aggregate is created
with all Ethernet cards capable of TCP Segmentation Offload (TSO).
•
Support for Virtual VLANs (VLANs) over APA link aggregates and failover groups.
•
Support for 64-bit MIB (RFC 2863) statistics, if all the interfaces within a link aggregate or
failover group support 64-bit statistics.
•
Support for IPv6 addresses on a link aggregate or failover group.
•
Support for the creation of failover groups over InfiniBand IPoIB ports. (March 2009 release
of APA for HP-UX 11i v3 (B.11.31.30) and later releases)
•
Support for the assignment of fixed MAC addresses for link aggregates and failover groups.
(January 2009 release of APA for HP-UX 11i v3 (B.11.31.40) and later releases)
For release-specific information, see the release notes on the web at:
http://www.docs.hp.com
For a summary of HP APA capabilities, see
Appendix A (page 87)
.
Conceptual overview
HP APA offers you a comprehensive solution to create fast, highly available network server
connections with minimal IT support costs. HP APA enables this with four key benefits:
•
Automatic link failure detection and recovery in case of network failures. A link aggregate
continues to operate as long as there is at least one port operating.
•
Scalable high-performance link aggregates using Fast or Gigabit Ethernet and the HP APA
load-balancing algorithms. See
“Load balancing” (page 10)
for more information.
•
Fault management and isolation with the HP MIB Monitor and
nettl
logging facilities.
•
Lower IT costs with automated configuration and management tools using the IEEE 802.3ad
or PAgP standards and the intuitive HP System Management Homepage (SMH) GUI.
This section describes the following features of HP APA:
•
Link aggregate
•
Failover group
•
TCP segmentation offload
•
VLAN support
•
Interoperability with HP Serviceguard
•
Administrative methods
Link aggregate
HP APA enables you to combine 2 to 8 physical link ports (up to 32 for LACP mode) into one
link aggregate. This gives the link aggregation a theoretical bandwidth of 8 times that of a single
physical link (32 times for LACP mode). A link aggregate has the following characteristics:
Conceptual overview
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