Specifications

Chapter 1 Product Overview
Recommended Configurations
1-28
Catalyst 4224 Access Gateway Switch Software Configuration Guide
OL-2031-02
Port Fast Not Enabled on Trunk Ports
You should configure ports as switched access ports. However, there may be
implementations where your requirements dictate configuring ports as trunks and
you want to standardize this configuration across all 24 ports. This is not the
recommended configuration. Because of DHCP request timeouts on Windows
95/NT, portfast may be a desirable feature. However, portfast is not supported on
ports in trunking mode. To reduce the forwarding delay time of a port, use the
global configuration commands for the specific VLAN and reduce the forwarding
timers to the minimum value of four seconds. See the following sample
configuration:
spanning-tree portfast bpduguard
spanning-tree vlan 60 forward-time 4
spanning-tree vlan 160 forward-time 4
These commands configure VLAN ports to forward data in eight seconds.
If you connect Catalyst 4224 to another switch, make sure that the timers are the
same value. Otherwise Spanning Tree issues may arise. Also note that only
802.1Q trunking is supported on the Catalyst 4224.
Priority Queuing on Frame Relay
Frame relay does not support LLQ/CBWFQ. The service policy output command
is currently disabled. Therefore, only ip rtp priority is supported as a voice
priority queuing scheme. FRF.12 is supported on frame relay links.
The recommended configuration for FRF.12 and ip rtp priority is shown in the
following procedure. The parameter values are for illustrative purposes only.
Your values may differ.
Step 1 Define the appropriate map class. The following sample configuration shows how
to define the map class:
map-class frame-relay VOIP_256
no frame-relay adaptive-shaping
frame-relay cir 250000
frame-relay bc 1000
frame-relay be 0
frame-relay mincir 250000
frame-relay fair-queue