Zyxel GS2200-24 Руководство пользователя онлайн [215/332] 810932

GS2200-8/24 User’s Guide 215

CHAPTER 26

Loop Guard

26.1 Overview

This chapter shows you how to configure the Switch to guard against loops on the edge of your

network.

Loop guard allows you to configure the Switch to shut down a port if it detects that packets sent out

on that port loop back to the Switch. While you can use Spanning Tree Protocol (STP) to prevent

loops in the core of your network. STP cannot prevent loops that occur on the edge of your

network.

Figure 134 Loop Guard vs. STP

Refer to Section 26.1.2 on page 215 for more information.

26.1.1 What You Can Do

Use the Loop Guard screen (Section 26.2 on page 217) to enable loop guard on the Switch and in

specific ports.

26.1.2 What You Need to Know

Loop guard is designed to handle loop problems on the edge of your network. This can occur when

a port is connected to a Switch that is in a loop state. Loop state occurs as a result of human error.

It happens when two ports on a switch are connected with the same cable. When a switch in loop

state sends out broadcast messages the messages loop back to the switch and are re-broadcast

again and again causing a broadcast storm.

If a switch (not in loop state) connects to a switch in loop state, then it will be affected by the

switch in loop state in the following way:

STP

Loop Guard