Installation guide

Release Notes for Catalyst5000 Family Software Release4.x

OL-2306-01

Usage Guidelines and Restrictions

Caution If you enable numerous memory-intensive features concurrently (such as VTP pruning, VMPS,

EtherChannel, and RMON), or if there is switched data traffic on the management VLAN, the

maximum number of supported logical ports is reduced.

Note Count each port in an EtherChannel port bundle independently (do not count the bundle

as a single port).

• When connecting end stations (such as Windows95/98/NT workstations) to 10/100-Mbps switch

ports, we recommend this configuration:

–

Spanning tree PortFast enabled

Use the set spantree portfast mod_num/port_num enable command to enable PortFast on a

port.

–

Trunking off

Use the set trunk mod_num/port_num off command to disable trunking on a port.

–

Channeling off

Use the set port channel port_list off command to disable channeling on a port.

Note You must specify a valid port range when entering the set port channel command. You

cannot specify a single port.

This example shows how to configure a port for end station connectivity:

Console> (enable) set spantree portfast 2/2 enable

Warning: Spantree port fast start should only be enabled on ports connected

to a single host. Connecting hubs, concentrators, switches, bridges, etc. to

a fast start port can cause temporary spanning tree loops. Use with caution.

Spantree port 2/2 fast start enabled.

Console> (enable) set trunk 2/2 off

Port(s) 2/2 trunk mode set to off.

Console> (enable) set port channel 2/1-2 off

Port(s) 2/1-2 channel mode set to off.

Console> (enable)

• In software release 4.x, the uplink ports on the standby supervisor engine are active (in software

release 4.3(1) and later you can disable this feature). If you are using the ports on the standby

supervisor, and you have configured those ports as trunk ports, make sure that traffic for no more

than 20 different VLANs will traverse the trunk.

Caution If traffic for more than 20 VLANs is carried on standby supervisor engine trunk ports, under certain

conditions, network loops can temporarily open, increasing spanning tree convergence time and

increasing network instability.