AT-S63 Management Software Features Guide
Section VII: Routing
363
Overview
This chapter describes the Virtual Router Redundancy Protocol (VRRP) of
the AT-9400 Basic Layer 3 Switches.
One of the functions that switches provide to the hosts of a LAN is to act
as gateways. The local hosts use the gateways to communicate with the
hosts on the WAN. The local hosts are assigned static routes that define
which gateway switch to use as the next hop to reach the WAN. However,
if a statically configured first hop switch fails, the hosts on the LAN will not
be able to communicate with the WAN. If there are a large number of
hosts, it can be time consuming and cumbersome if you have to
reconfigure the static routes on all of the affected hosts.
The Virtual Router Redundancy Protocol provides a solution to the
problem. It combines two or more physical switches into a logical grouping
called a
virtual router
(VR). The physical switches in the virtual router
operate together to provide a single logical gateway for hosts on the LAN
so that if one gateway fails, the hosts will still be able to communicate with
the WAN.
Summary of Contents for AT-S63
Page 14: ...Figures 14 ...
Page 18: ...Tables 18 ...
Page 28: ...28 Section I Basic Operations ...
Page 58: ...Chapter 1 Overview 58 ...
Page 76: ...Chapter 2 AT 9400Ts Stacks 76 Section I Basic Operations ...
Page 96: ...Chapter 5 MAC Address Table 96 Section I Basic Operations ...
Page 114: ...Chapter 8 Port Mirror 114 Section I Basic Operations ...
Page 116: ...116 Section II Advanced Operations ...
Page 146: ...Chapter 12 Access Control Lists 146 Section II Advanced Operations ...
Page 176: ...Chapter 14 Quality of Service 176 Section II Advanced Operations ...
Page 196: ...196 Section III Snooping Protocols ...
Page 204: ...Chapter 18 Multicast Listener Discovery Snooping 204 Section III Snooping Protocols ...
Page 216: ...Chapter 20 Ethernet Protection Switching Ring Snooping 216 Section III Snooping Protocols ...
Page 218: ...218 Section IV SNMPv3 ...
Page 234: ...234 Section V Spanning Tree Protocols ...
Page 268: ...268 Section VI Virtual LANs ...
Page 306: ...Chapter 27 Protected Ports VLANs 306 Section VI Virtual LANs ...
Page 320: ...320 Section VII Internet Protocol Routing ...
Page 360: ...Chapter 30 BOOTP Relay Agent 360 Section VII Routing ...
Page 370: ...Chapter 31 Virtual Router Redundancy Protocol 370 Section VII Routing ...
Page 372: ...372 Section VIII Port Security ...
Page 402: ...Chapter 33 802 1x Port based Network Access Control 402 Section VIII Port Security ...
Page 404: ...404 Section IX Management Security ...
Page 436: ...Chapter 36 PKI Certificates and SSL 436 Section IX Management Security ...
Page 454: ...Chapter 38 TACACS and RADIUS Protocols 454 Section IX Management Security ...
Page 462: ...Chapter 39 Management Access Control List 462 Section IX Management Security ...
Page 532: ...Appendix D MIB Objects 532 ...