ATM Configuration and Troubleshooting Guide

Configuring EMS High Availability over ATM
Configuration Recommendations
Chapter 6110
Configuration Recommendations
To eliminate single point of failure (SPOF) in a system containing ATM
adapters, Hewlett-Packard recommends you follow these guidelines
when designing your ATM network for High Availability:
• For local recovery:
— Configure your ATM network so that ATM adapters are always
backed up by identical adapters.
— Install at least two identical ATM adapters per system.
One exception to this recommendation exists: Hewlett-Packard
supports local recovery when the primary ELAN interface is
configured on a J2468A (ATM-HSC 622 Mbit/s) adapter and the
secondary interfaces are configured on a J2469A (ATM-HSC 155
Mbit/s [+]) adapter. However, because of the difference in
transfer rates between these two adapters, only the UBR traffic
parameter is supported in this configuration. (Although the
J2468A adapter is discontinued, this information is still included
for backwards compatibility.) Note that when different types of
cards are configured as primary and secondary, a warning
appears while you are in SAM.
— Configure at least two separate ATM switches in your network.
— Connect the primary and secondary adapters to different
switches.
— Provide secondary LAN Emulation Services.
— Place the LAN Emulation Services in a device that is not directly
connected to a system that is part of the High Availability
cluster. This avoids losing both the switch and LAN Emulation
Services simultaneously if the switch fails. Recovery from two
defective functions can take up to 10 minutes.
• For remote recovery:
— Use remote recovery in conjunction with local recovery (follow all
of the guidelines listed for local recovery, above).