ATM Configuration and Troubleshooting Guide

Troubleshooting
Troubleshooting MPOA
Chapter 9254
IMPORTANT HP’s implementation of ATM does not support MPOA for Token Ring
networks. This is because of a lack of MPOA Server (MPS) support for
Token Ring in routers.
Also, HP’s implementation does not support MPOA for secondary LANs.
To use the MPOA feature, you should first make sure that all of the
components of your ATM network that are involved in establishing the
MPOA shortcuts are MPOA-capable and have had their MPOA
capability configured and turned on. These components include the HP
host systems (which must be configured for MPOA [see “For Ethernet
and Token Ring Networks” on page 53]), the devices hosting the LANE
Version 2 services (especially the LECS—which will provide many of the
MPOA-specific configuration parameters—and the LES and BUS), the
routers, and the edge devices.
In this troubleshooting example, the flow detection threshold has been
set to one packet every two seconds, to allow us to use ping to establish
shortcuts. In a real-world configuration, an MPOA flow definition can be
dozens or hundreds of packets per second. In that case, ping becomes
inadequate as a means to generate traffic. However, when you are
troubleshooting MPOA, we recommend you lower the threshold, to be
able to use ping as a simple tool to generate a traffic volume sufficient
for shortcut establishment. See your routers’ and edge devices’
documentation for LANE V2 and MPOA parameter modification.
Assumptions. This procedure assumes the following:
✓ The LAN Emulation (LANE) interfaces ofboth end systems belong to
a different ELAN and are on a different IP subnet.
✓ For a bidirectional shortcut, the LANE interfaces of both end
systems have the same MTU Size (see “K” on page 264).
✓ You have one or more MPOA-capable gateways to route the traffic
between the subnets. If you do not, you cannot use the MPOA
feature of the HP ATM software.
✓ You have made sure that all of the devices in the MPOA network are
MPOA-capable and have had that capability turned on.
✓ You have lowered the flow detection threshold to a setting that
makes it possible to use the ping command to generate adequate
traffic for an MPOA data flow (as recommended above).