Chapter 23: Multiple Spanning Tree Protocol
250
Section V: Spanning Tree Protocols
Multiple Spanning Tree Instance (MSTI)
The individual spanning trees in MSTP are referred to as Multiple
Spanning Tree Instances (MSTIs). A MSTI can span any number of
AT-9400 Switches. The switch can support up to 16 MSTIs at a time.
To create a MSTI, you first assign it a number, referred to as the MSTI ID.
The range is 1 to 15. (The switch is shipped with a default MSTI with an
MSTI ID of 0. This default spanning tree instance is discussed later in
“Common and Internal Spanning Tree (CIST)” on page 260.)
After you have selected an MSTI ID, you need to define the scope of the
MSTI by assigning one or more VLANs to it. An instance can contain any
number of VLANs, but a VLAN can belong to only one MSTI at a time.
Following are several examples. Figure 26 illustrates two AT-9400
Switches, each containing the two VLANs Sales and Production. The two
parts of each VLAN are connected with a direct link using untagged ports
on both switches. If the switches were running STP or RSTP, one of the
links would be blocked because the links constitute a physical loop. Which
link would be blocked depends on the STP or RSTP bridge settings. In
Figure 26, the link between the two parts of the Production VLAN is
blocked, resulting in a loss of communications between the two parts of
the Production VLAN.
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 ...