HP 2610-PWR 113

Spanning-Tree Operation

Overview

Without spanning tree, having more than one active path between a pair of nodes causes loops in the network, which can result in duplication of mes sages, leading to a “broadcast storm” that can bring down the network.

Single-Instance spanning tree operation (802.1D STP and 802.1w RSTP) ensures that only one active path at a time exists between any two nodes in a physical network. In networks where there is more than one physical, active path between any two nodes, enabling single-instance spanning tree ensures one active path between such nodes by blocking all redundant paths.

Multiple-Instance spanning tree operation (802.1s) ensures that only one active path exists between any two nodes in a spanning-treeinstance. A spanning-tree instance comprises a unique set of VLANs, and belongs to a specific spanning-treeregion. A region can comprise multiple spanning-tree instances (each with a different set of VLANs), and allows one active path among regions in a network. Applying VLAN tagging to the ports in a multiple- instance spanning-tree network enables blocking of redundant links in one instance while allowing forwarding over the same links for non-redundant use by another instance. For example, suppose you have three switches in a region configured with VLANs grouped into two instances, as follows:

VLANs	Instance 1	Instance 2
10, 11, 12	Yes	No
20, 21, 22	No	Yes

5-5

Contents

ProCurve Switches Page ProCurve Switch 2610 Series Switch 2610-PWRSeries Advanced Traffic Management Guide Page Product Documentation 1 Getting Started 2 Static Virtual LANs (VLANs) 3 GVRP 4 Multimedia Traffic Control with IP Multicast (IGMP) 5 Spanning-TreeOperation 6Quality of Service (QoS): Managing Bandwidth More Effectively Page 7 IP Routing Features 8 ProCurve Stack Management Index Page Product Documentation Software Feature Index Page Page Page Page Getting Started Conventions bold italics Series 2610 Switches copy tftp hostname Figure 1-1.Example of a Figure Showing a Simulated Screen Sources for More Information www.procurve.com Technical support, and then click on Product manuals Figure 1-2.Getting Help in the Menu Interface Need Only a Quick Start setup 8.Run Setup Important Static Virtual LANs (VLANs) Page Page Port-BasedVirtual LANs (Static VLANs) N o t e Table 2-1.VLANMaximums Figure 2-1.Example of Routing Between VLANs via an External Router Figure 2-2.Example of Overlapping VLANs Using the Same Server Figure 2-3.Example of Connecting Multiple VLANs Through the Same Link Introducing Tagged VLAN Technology into Networks Running Legacy (Untagged) VLANs Figure 2-4.Example of Tagged and Untagged VLAN Technology in the Same Network show vlan Figure 2-5.Comparing Per-PortVLAN Options With and Without GVRP Table 2-2. Per-PortVLAN Configuration Options Forbid Page Table 2-6.Example of Forwarding Database Content Table 2-7.Forwarding Database Structure for Managed ProCurve Switches Page Page The Solution 2.Switch Configuration 8.VLAN Menu 1.VLAN Support Figure 2-11.The Default VLAN Support Screen GVRP Enabled [S] Maximum VLANs to support Figure 2-12.VLAN Menu Screen Indicating the Need To Reboot the Switch [0] 2.VLAN Names Figure 2-13.The Default VLAN Names Screen [A] Name : Name Figure 2-14.Example of VLAN Names Screen with a New VLAN Added 2. Switch Configuration 3.VLAN Port Assignment Figure 2-15.Example of VLAN Port Assignment Screen Untagged, or Forbid) For GVRP Operation: Figure 2-16.Example of VLAN Assignments for Specific Ports VLAN Commands Used in this Section Figure 2-17.Example of “Show VLAN” Listing (GVRP Enabled) Syntax Figure 2-18.Example of “Show VLAN” for a Specific Static VLAN Figure 2-19.Example of “Show VLAN” for a Specific Dynamic VLAN show vlan ports detail a1-a16 all detail Port name: Figure 2-20.Example of “Show VLAN Ports” Cumulative Listing Figure 2-21.Example of “Show VLAN Ports” Detailed Listing Figure 2-22.Example of Command Sequence for Changing the Number of VLANs Figure 2-23.Example of Creating a New Static VLAN Auto VLAN already exists 2.Click on VLAN Configuration 3.Click on Add/Remove VLANs Figure 2-24.Example of Tagged and Untagged VLAN Port Assignments Figure 2-25.Example of VLAN ID Numbers Assigned in the VLAN Names Screen Figure 2-26.Example of Networked 802.1Q-CompliantDevices with Multiple VLANs on Some Ports Switch Switch Y Page Figure 2-27.Example of Potential Security Breaches Figure 2-28.Example of Management VLAN Control in a LAN Table 2-3.VLAN Membership in Figure DHCP/Bootp Manual write memory Default: Disabled running-config Figure 2-29.Illustration of Configuration Example write-memory Implementing Spanning Tree Page Page GVRP Page Page Figure 3-1.Example of Forwarding Advertisements and Dynamic Joining Figure 3-2.Example of GVRP Operation IP Addressing Table 3-1.Options for Handling “Unknown VLAN” Advertisements: show gvrp Figure 3-3.Example of GVRP Unknown VLAN Settings Page Table 3-2.Controlling VLAN Behavior on Ports with Static VLANs Page Page 2.Switch Configuration Figure 3-4.The VLAN Support Screen (Default Configuration) Unknown VLAN Figure 3-5.Example Showing Default Settings for Handling Advertisements GVRP Commands Used in This Section Figure 3-6.Example of “Show GVRP” Listing with GVRP Disabled Figure 3-7.Example of Show GVRP Listing with GVRP Enabled Enabling and Disabling GVRP on the Switch. This command enables Syntax: gvrp Figure 3-8.Example of Preventing Specific Ports from Joining Dynamic VLANs Figure 3-9.Example of Switches Operating with GVRP Enabled show vlans Figure 3-10.Example of Listing Showing Dynamic VLANs VLAN Configuration GVRP Security Apply Page Page Multimedia Traffic Control with IP Multicast (IGMP) Page General Operation and Features IGMP Device: IGMP Host: Forward with High Priority Auto/Blocked/Forward: Auto Blocked: Forward: CLI: Configuring and Displaying IGMP Figure 4-1.Example Listing of IGMP Configuration for All VLANs in the Switch show ip igmp Figure 4-2.Example Listing of IGMP Configuration for A Specific VLAN ip igmp Page Web: Enabling or Disabling IGMP Device Features Apply Changes How IGMP Operates querier Report (Join): Leave Group: Page Table 4-1.Comparisonof IGMP Operation With and Without IP Addressing Fast-Leave IGMP 4-2.SwitchesSupported for IGMP Features Automatic Fast-LeaveOperation. If a switch port is: Figure 4-3.Example of Automatic Fast-LeaveIGMP Criteria Page show configuration N o t e o n V L A N N u m b e r s walkmib setmib To List the Forced Fast-LeaveState for a Single Port. (See the “Note getmib VLAN Figure 4-6.Example of Changing the Forced Fast-LeaveConfiguration on Port Using the Switch as Querier Excluding Multicast Addresses from IP Multicast Filtering 4-3.IPMulticast Address Groups Excluded from IGMP Filtering Reserved Addresses Excluded from IP Multicast (IGMP) Filtering Page Spanning-TreeOperation Page Table 5-1.STP Support Table 5-3.802.1w RSTP Features Table 5-4.802.1s Features Page Figure 5-1.Example of a Multiple Spanning-TreeApplication Note for 802.1D and 802.1w Spanning-TreeOperation C a u t i o n The RSTP (802.1w) and STP (802.1D) Spanning Tree Options Page Figure 5-2.General Example of Redundant Paths Between Two Nodes Figure 5-3.Example of Using a Trunked Link with STP and VLANs Configuring Rapid Reconfiguration Spanning Tree (RSTP) Force Version on page Menu CLI: Menu: Viewing the Current Spanning Tree Configuration. Use this command sho span config Figure 5-4.Example of the Spanning Tree Configuration Display Enabling or Disabling RSTP Abbreviation: [no] span Enabling STP Instead of RSTP Abbreviation: span prot stp Reconfiguring Whole-SwitchSpanning Tree Values. You can configure Table 5-1. Whole-SwitchRSTP Parameters Abbreviations: Per-PortRSTP Parameters Abbreviations: Note on Path Cost menu 2.Switch Configuration … 4.Spanning Tree Operation Protocol Version RSTP or STP Figure 5-5.Example of the RSTP Configuration Screen Actions elp 6. Reboot Switch Page 802.1D Spanning-TreeProtocol (STP) Figure 5-6.The Default “Spanning Tree Operation” Screen Figure 5-7.Enabling Spanning-TreeOperation Actions line Page Viewing the Current STP Configuration Figure 5-10.Example of the Default STP Configuration Listing with 802.1D STP Configured at the Protocol Version stp Figure 5-11.Steps for Changing Spanning-TreeOperation to the 802.1D Protocol Enabling (or Disabling) Spanning Tree Operation on the Switch Table 5-3.General STP Operating Parameters Reconfiguring Per-PortSTP Operation on the Switch fast Page Figure 5-12.Example of How To Implement Fast-UplinkSTP Page Table 5-5.STP Parameter Settings for Figure Scenario 1: Scenario 2: Figure 5-14.Example of a Disallowed Connection Between Edge Switches STP Priority Page [E] Figure 5-16.Changing from RSTP to STP Requires a System Reboot STP Figure 5-17.The Spanning Tree Operation Screen To View STP Status 1.Status and Counters … 7.Spanning Tree Information Page Figure 5-21.Example Topology for the Listing Shown in Figure Page Page Page Norm Web: Enabling or Disabling STP 2.Click on [Device Features] [Apply Changes] 802.1s Multiple Spanning Tree Protocol (MSTP) Figure 5-25.Example of MSTP Network with Legacy STP and RSTP Devices Connected Internal Page Figure 5-26.Active Topologies Built by Three Independent MST Instances Page Connectivity within the Same MST Instance Bridge: Common Spanning Tree (CST): Internal Spanning Tree (IST): MST Region: Page STP-compatible force version Page Spanning Tree protocol-version < stp | rstp | mstp Region Name: spanning-tree config-name Region Revision Number: spanning-treeconfig revision spanning-tree forward-delay max-age spanning-treepriority spanning-treeinstance < 1 - 16 > vlan < vid no spanning- tree instance Page spanning-tree pending stp-compatible: rstp-operation: mstp-operation: mstp force-version Page The no spanning-tree< port-list > mcheck ] command disables mcheck Force-True default) Force-False Auto: tcn-guard Switch Priority Page Page show running Priority instance ist > instance ist Page config-revision show spanning- tree pending a20-trk1 Figure 5-28.Example of Common Spanning Tree Status on an MSTP Switch Displaying Switch Statistics for a Specific MST Instance Page show spanning-tree a20-trk1config instance Figure 5-31.Example of the Configuration Listing for a Specific Instance Figure 5-32.Example of a Region-LevelConfiguration Display Figure 5-33.Example of Displaying a Pending Configuration Duplicate packets on a VLAN, or packets not arriving on a LAN at all A Switch Intended To Operate Within a Region Does Not Receive Page Quality of Service (QoS): Managing Bandwidth More Effectively Page Page Honor Priority Honor New Priority Set Priority Set Policy Honor Policy 802.1p prioritization: Type-of-Service (ToS): Page Table 6-1.PortQueue Exit Priorities Table 6-2.QoS Priority Settings and Operation Table 6-3.MappingSwitch QoS Priority Settings to Device Queues M u l t i p l e C r i t e r i a Table 6-4.Switch Classifier Search Order and Precedence Table 6-5.PrecedenceCriteria for QoS Classifiers Page Preparation for Configuring QoS Table 6-6.Summary of QoS Capabilities Table 6-7.Applying QoS Options to Traffic Types Defined by QoS Classifiers Table 6-8.QoS Rule Resource Usage Page Configuring a Policy When There Are Not Enough Rules Available Adding a Port to a QoS-ConfiguredVLAN Without Enough Rules show qos resources Figure 6-3.Example of Inspecting Available Rule Resources Demonstrating Differing Resource Usage on Different Ports Figure 6-4.Example of QoS Resource Usage with Device-Priorityand VLAN QoS Page Using QoS Classifiers To Configure QoS for Outbound Traffic Figure 6-5.Example of the Show QoS Output for VLAN Priority QoS Classifier Precedence: Options for Assigning Priority TCP/UDP Port Number Ranges. There are three ranges: www.iana.org Protocol Number Assignment Services Port Numbers Page N o t e o n P o l i c y Ty p e s Steps for Creating a DSCP Policy Based on TCP/UDP Port Number Classifiers Page Figure 6-7.Display the Current DSCP-MapConfiguration Figure 6-8.Assign Priorities to the Selected DSCPs Page Page Page Page Figure 6-11.Display the Current DSCP-MapConfiguration Figure 6-12.Assigning 802.1p Priorities to the Selected DSCPs Figure 6-13.The Completed Device-Priority/CodepointConfiguration ■ ToS Differentiated Services (Diffserv) Mode: This mode requires • Assign a New Prioritization Policy: A “policy” includes both a Assign an 802.1p Priority: Figure 6-14.Example of Enabling ToS IP-PrecedencePrioritization diff services 4.Enable diff-services diff-services Page incoming-DSCP outgoing- DSCP Page Figure 6-18.Display the Current DSCP-MapConfiguration qos dscp map N o t e s Figure 6-21.The ToS Codepoint and Precedence Bits Table 6-9.How the Switch Uses the ToS Configuration Table 6-10.ToS IP-PrecedenceBit Mappings to 802.1p Priorities Page Figure 6-22.Example of a List of VLANs Available for QoS Prioritization Figure 6-23.Configuring and Displaying QoS Priorities on VLANs Figure 6-24.Returning a QoS-PrioritizedVLAN to “No-override”Status Steps for Creating a Policy Based on VLAN-IDClassifier Figure 6-25.Display the Current Configuration in the DSCP Policy Table Figure 6-26.Assign Priorities to the Selected DSCPs Figure 6-27.The Completed VID-DSCPPriority Configuration Page Figure 6-28.Configuring and Displaying Source-PortQoS Priorities Figure 6-29.Returning a QoS-PrioritizedVLAN to “No-override”Status Page Page Figure 6-30.Display the Current Configuration in the DSCP Policy Table Figure 6-31.Assign Priorities to the Selected DSCPs Figure 6-32.The Completed Source-Port DSCP-PriorityConfiguration No- override Table 6-11.TheDefault DSCP Policy Table > priority < 0 - 7 >) Page Cannot modify DSCP Policy < codepoint > - in use by other qos rules show qos classifier Figure 6-34.Example of Trying To Change the Priority on a Policy In Use by a Classifier device-priority port-priority udp-port IP Multicast (IGMP) Interaction with QoS QoS Messages in the CLI QoS Operating Notes and Restrictions Table 6-12.Details of Packet Criteria and Restrictions for QoS Support All Switches: For Devices that Do Not Support 802.1Q Port Tagging Rules: Maximum QoS Configuration Entries: All Switches—Not Supported: Page IP Routing Features Page Overview of IP Routing Figure 7-1.Example of a Dynamic Entry show ip route Figure 7-2.Example of IP Route Table Entry Table 7-1.IP Global Parameters for Routing Switches Table 7-2.IP Interface Parameters – Routing Switches Configuring IP Parameters for Routing Switches Page infinite arp-age Default Figure 7-3.Example of Setting the ARP Age Timeout to 1000 Minutes show ip Figure 7-4.Example of show ip Command Displaying Arp Age Figure 7-5.Example Showing ip arp-ageValue in the Running Config File Figure 7-6.Example of the Menu Interface Displaying the Arp Age Value clear arp Page Burst-Normal Reply Limit Echo messages Address Mask replies Administration Fragmentation-needed Host Network Port Configuring Static IP Routes Directly-connected Statically configured route Null (reject) reject Page Page Figure 7-7.Example of a Routed Network Figure 7-8.Examples of the Show IP Route Command Configuring IRDP Packet type Hold time Page broadcast Figure 7-9.Example of Displaying IRDP Information Configuring DHCP Relay Page Page Figure 7-10.Example of a DHCP Option 82 Application DHCP Policy Boundary: DHCP relay agent: See Relay Agent Primary Relay Agent: Relay Agent: Secondary Relay Agent: Page Remote ID: system-information Figure 7-12.Usingthe CLI To View the Switch MAC Address Circuit ID: walkmib ifname append replace drop Configuration Options for Managing DHCP Client Request Packets Page Page Table 7-4.Relay Agent Management of DHCP Server Response Packets append: replace: keep: ip: Page Page UDP Broadcast Forwarding Page ip forward protocol udp forward-protocol udp dns: ntp: netbios-ns: netbios-dgm: radius: Figure 7-17.Displaying Global IP Forward-ProtocolStatus and Configuration Figure 7-18.Displaying IP Forward-ProtocolStatus and Per-VLANConfiguration Page Page ProCurve Stack Management Page Page Operation Page Table 8-1.Stacking Definitions Figure 8-1.Illustration of a Switch Moving from Candidate to Member Network Interface Options Figure 8-3.Example of a Non-StackingDevice Used in a Stacking Environment Table 8-2.Specific Rules for Commander, Candidate, and Member Switch Page Configuring Stack Management N/A Stack State Candidate General Steps for Creating a Stack Figure 8-4.Using the System Name to Help Identify Individual Switches Stacking Figure 8-5.The Default Stacking Menu Stack Configuration Figure 8-6.The Default Stack Configuration Screen Edit Yes Save Table 8-4.Candidate Configuration Options in the Menu Interface Transmission Interval Using the Menu To “Push” a Switch Into a Stack, Modify the Switch’s Figure 8-8.The Default Stack Configuration Screen Transmission Interval Using the Commander’s Menu To Manually Add a Candidate to a Stack 9.Stacking 4.Stack Management Figure 8-9.Example of the Stack Management Screen Add Figure 8-10.Example of Candidate List in Stack Management Screen Figure 8-11.Example of Stack Management Screen After New Member Added Using the Commander’s Menu To Move a Member From One Stack to 2.Stacking Status (All) Back Page Figure 8-13.Example of Stack Management Screen with Stack Members Listed Figure 8-14.Example of Selecting a Member for Removal from the Stack Delete Figure 8-15.The Prompt for Completing the Deletion of a Member from the Stack 5.Stack Access Figure 8-16.Example of the Stack Access Screen eXecute 9.Stacking ack 3.Stack Configuration Member Com mander MAC Address Table 8-5.Stack Status Environments Viewing Commander Status 1.Stacking Status (This Switch) Figure 8-19.Example of the Commander’s Stacking Status Screen Figure 8-20.Example of a Member’s Stacking Status Screen Viewing Candidate Status Figure 8-21.Example of a Candidate’s Stacking Screen Table 8-6.CLI Commands for Configuring Stacking on a Switch Page Viewing the Status of Candidates the Commander Has Detected Figure 8-23.Example of Using the Show Stack Candidates Command To List Candidates Viewing the Status of all Stack-EnabledSwitches Discovered in the IP Viewing the Status of the Commander and Current Members of the Commander’s Stack Page Using a Member’s CLI to Convert the Member to the Commander of a Page Using the Commander’s CLI To Manually Add a Candidate to the show stack view show stack candidates Figure 8-28.Example of How To Determine Available Switch Numbers (SNs) Figure 8-29.Example of How To Determine MAC Addresses of Discovered Candidates Figure 8-30.Example Showing the Stack After Adding a New Member Status: [no] stack auto-join Status: Using a Candidate CLI To Manually “Push” the Candidate Into a Stack mac-addr Figure 8-31.Example of “Pushing” a Candidate Into a Stack Using the Destination Commander CLI To “Pull” a Member from Figure 8-32.Example of Stack Listing with Two Stacks in the Subnet show stack all Figure 8-33.Example of Command Sequence for Converting a Commander to a Member Figure 8-34.Example of a Commander and Three Switches in a Stack Using the Member’s CLI To Remove the Member from a Stack 1 - 15) Figure 8-36.Example of a Stack Showing Switch Number (SN) Assignments Figure 8-37.Example of SNMP Community Operation with Stacking SNMP Management Station Access to Members Via the Commander @sw<switch number Disabling a Candidate: Figure 8-38.Example of the Web Browser Interface for a Commander Stack Closeup Page Page Numerics