Cisco Catalyst 3550 User Manual

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Catalyst 3550 Multilayer Switch Command Reference
OL-8566-01
Chapter 2 Catalyst 3550 Switch Cisco IOS Commands
skip-loopback-test
skip-loopback-test
Use the skip-loopback-test interface configuration command to configure the switch to omit the
loopback test on an interface during the switch power-on self-test (POST).
skip-loopback-test
no skip-loopback-test
Syntax Description This command has no arguments or keywords.
Defaults A loopback test is performed on all interfaces during POST.
Command Modes Interface configuration
Command History
Usage Guidelines Use this command in rare situations when an interface fails POST but the switch hardware is known to
be fully functional as is the case when the Gigabit port of a Catalyst 3550 switch with inline power
(WS-C3550-25-PWR) is connected to the Gigabit port of a Catalyst 4000 series switch with Supervisor
Model WS-X4516 running Cisco IOS release 12.2(18)EW or 12.2(20)EW. This configuration is known
to experience lost loopback packets when the switch boots up and entering this command on the interface
allows it to remain up.
Release Modification
12.2(37)SE This command was introduced.

Cisco Catalyst 3550 Specifications

General

Category	Switch
QoS	Yes
Form Factor	Rack-mountable
Manageable	Yes
RAM	64 MB
Model	Catalyst 3550
Uplink Ports	2 x GBIC (Gigabit Interface Converter) or SFP (Small Form-factor Pluggable)
Layer Support	Layer 3
VLAN Support	Yes
MAC Address Table Size	12000 entries
Routing Protocol	EIGRP
Features	QoS
Operating Temperature	32 to 113°F (0 to 45°C)
Operating Humidity	10 - 95% (non-condensing)
Ports	24 or 48 10/100 ports