What is APA ? How to configure APA using nwmgr utility?

By Guna :

What is APA ?

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.

HP APA provides the following

• 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.

Verify APA is installed on your system?

1. Verify that the product was installed by issuing the following command:
# swlist -l product | grep -i HP-APA

Output similar to the following displays:
HP-APA-FMT B.11.31.20 HP Auto-Port Aggregation APA formatter product.
HP-APA-KRN B.11.31.20 HP Auto-Port Aggregation kernel products.
HP-APA-LM B.11.31.20 HP Auto-Port Aggregation LM commands.
HP-APA-NETMOD B.11.31.20 HP Auto-Port Aggregation nwmgr/NCweb libraries.
HP-APA-RUN B.11.31.20 HP Auto-Port Aggregation APA command products.

2. Verify that the software is configured in the kernel by issuing the following command:
# what /stand/vmunix | egrep -i hp_apa
Output similar to the following displays:
$Revision: hp_apa: HP Auto-Port Aggregation (APA): B.11.31.20 Aug 20 2008 11:30
If nothing is displayed, rebuild the kernel.

Configure APA using nwmgr :

Step 1 : Check first if any APA is already configured

# nwmgr -S apa

Note: If LAN_MONITOR is enabled you need to remove that (Its only required when you are planning to have failover capability over APA.)

Delete failover group first
# nwmgr -d -S apa -A links=all -c lan900
# nwmgr -s -S apa -A all --saved --from cu

Step 2 : Check 1st lan Interface status

#ifconfig lan3
#ifconfig lan3 unplumb
#ifconfig lan4
#ifconfig lan4 unplumb
#netstat -in

Step 3 : Create Link Aggregate.

#nwmgr -a -S apa -c lan900 -A links=3,4 -A mode=MANUAL -A lb=LB_MAC
Save configuration.

# nwmgr -s -S apa -A all --saved --from cu
Check status of newly created link aggregate.
#nwmgr -S apa -I 900 -A all

Step 4 : Configure IP addrss to link aggregate (lan900) and change the netconf file.

#vi /etc/rc.confg.d/netconf

Then add the IP address and save the file.

Step 5 : Restart APA.

#/sbin/init.d/hpapa stop
#/sbin/init.d/hpapa start

Step 6 : # Check IP configuration

#netstat -in

Post a Comment


  1. nice post-it, thank you!

  2. using the given steps I created an apa on lan900 with ports 2,6,8 and 10.
    but when I execute lanadmin -x -v it gives only partial information, and instead of link aggregation state/group capability/load balance mode it give Memory Fault(coredump)

    # lanadmin -x -v 900
    Link Aggregate PPA # : 900
    Number of Ports : 4
    Ports PPA : 2 6 8 10
    Memory fault(coredump)