Avaya Cajun P580, Руководство пользователя, Страница: 430 / 770

13-20 User Guide for the Avaya P580 and P882 Multiservice Switches, v6.0
Chapter 13
determined the destination, it updates the L3 forwarding cache on
the F-chips with the L3FE. Once updated, the F-chip can forward
future packets via Fast Path.
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SA: Source IP Address.
■
Slow Path: When an ingress F-chip does not recognize a packet
compared to its cache of known Flows, the packet is forwarded to
the CPU to determine proper destination and ACL Rule assignment.
Optimizing Performance when Using ACLs
There are several techniques to optimize performance. They are related and
must be considered together.
■
Recognize Performance Issues
■
Evaluate System Performance
■
Enable Routing at the Module
■
Design Safe, Efficient ACLs
■
Identify the Ports
■
Configuring Hash Mode
■
Managing F-chip Memory
Recognize Performance Issues
When the ACL is the root of a performance problem, it shows as the Slow
Path becoming overused. The Slow Path is not designed to handle
significant traffic levels since the single CPU also handles all other
management functions. There are several ways to determine if the CPU is
overloaded:
■
Continuous PING to the supervisor: timeouts or inconsistent timing
of echo responses.
■
Slow Scrolling LED Marquee: This is good visual sign that the CPU
is busy.
■
Slow Management response: If Avaya Multiservice Network
Manager (MSNM), Avaya Policy Manager (APM), HPOV, or a MIB
browser get slow updates, this can signify a busy CPU or saturated
network.
■
Slow network response: This can be measured in a variety of ways.