HP Auto Port Aggregation Administrator's Guide HP-UX 11i v3 (766140-001, March 2014)

If you suspect or know that you are experiencing packet loss over your
connection, do the following:
1. LACP mode link aggregates require time to negotiate with the switch.
You might drop some packets during this time.
2. Check the trunk is configured correctly on the switch. Make sure
that ports connected to the ports on the server are assigned to the
LACP trunk. If the LACP trunk is assigned to any other ports on the
server, this can cause packets to be dropped.
3. Check the switch port configuration. Remove any port that is not
supposed to be in the trunk.
Problem still exists?
Report your problem to
4. Verify the link aggregate membership. See the steps for Link
aggregate enabled?. If the number of ports in the link aggregate is
greater than the maximum number of ports in the LACP trunk on the
switch, delete the extra ports from the LACP link aggregate.
HP. See “Reporting
problems ” (page 71).
Solving link aggregate problems (FEC mode)
Verify that the switch is configured correctly. See the appropriate switch
documentation to determine if the switch ports connected to the server
are configured correctly for link aggregation (trunking) and support the
FEC protocol.
Verify that the link aggregate is configured by issuing the nwmgr
command. Link aggregate names begin with lan900 (lan900, lan901,
...) and have the Subsystem as hp_apa.
If the link aggregate is not configured, use the System Management
Homepage to configure it. See “Configuring a link aggregate” (page 27)
for more information.
Verify that the link aggregate is configured by issuing the lanscan
command. Link aggregate names begin with LinkAgg.
If the link aggregate is not configured, use SAM to configure it. See
“Configuring a link aggregate” (page 27) for more information.
Verify that the link aggregate is enabled by issuing the following
command:
# nwmgr -v -I xxx -S apa
where xxx is the link aggregate instance number.
If the aggregate is enabled, the APA State is Up. This also indicates
that the FEC automatic protocol negotiation was successful.
If the APA State is Down, do the following:
1. Verify that all ports in the aggregate are set to the same mode using
the following command:
# nwmgr -A mode,gc -I xxx -S apa
where xxx is the port instance number (for example, 1,4, and 10).
If they are not, use the System Management Homepage (SMH) to
modify the aggregate. See “Modifying a link aggregate” (page 32)
for more information.
58 Troubleshooting HP APA