Cabletron Systems 9A128-01 manual Changing Max Age Time, Changing Forwarding Delay Time

Page 73

Bridging

Changing Max Age Time

If the selected module is the Root Bridge or attempting to become the Root, and you want to change the maximum time that bridge protocol information will be kept before it is discarded:

1.Highlight the Max Age field, and type in a new value.

2.Click on Set.

The IEEE 802.1d specification recommends that Max Age = 20 seconds; the allowable range is 6 to 40 seconds.

Changing Forwarding Delay Time

If the selected module is the Root Bridge or attempting to become the Root, and you want to change the time period the bridge will spend in the Listening state (e.g. either listening to BPDU activity on the network while moving from the Blocking to the Learning state or in the Learning state while the bridge is moving from the Listening to the Forwarding state):

1.Highlight the Forwarding Delay field, and type in a new value.

2.Click on Set.

The IEEE 802.1d specification recommends that Forward Delay = 15 seconds; the allowable range is 4 to 30 seconds.

NOTE

To ensure proper operation of the Spanning Tree Algorithm, the IEEE 802.1d specification recommends that you always observe the following relationship between Forwarding Delay and Max Age:

2 x (Forwarding Delay - 1.0) > Max Age

Changing Port Priority

To change the part of the Port Priority used in priority comparisons:

1.If necessary, select the desired port by clicking the mouse to highlight the port in the lower right quadrant of the window. The lower left quadrant of the window will now allow you to edit parameters for the selected port.

2.Highlight the port Priority field, and enter the new priority identifier. Only valid hexadecimal numbers (0 to FF) are allowed in this field. The default is 80 hexadecimal.

3.Click on Set. The new port priority will be saved.

5-20

Bridge Spanning Tree

Image 73
Contents Cabletron Systems Virus Disclaimer Page Restricted Rights Notice Page Contents Chapter Bridging Chapter Fddi ManagementIndex Introduction Using This GuideRelated Reading Common Window Fields Software ConventionsDevice Name IP AddressUsing On-line Help Using ButtonsGetting Help LocationFTP Getting Help from the Cabletron Systems Global Call CenterFirmware Versions Supported 9A128-01 Module View Front Panel Information Viewing Module InformationConnection Status Boot PromUpTime Port StatusTime Menu StructureDate Device Menu A128-01 Module View Menu StructurePort Status Menu Utilities Menu Fddi MenuHelp Menu Board MenusPort Menus Port Status DisplaysBridge Port Status Displays Selecting a Port Status ViewBridge Mapping Bridge Port StateBridge Port Status Color Codes Fddi Port Status DisplaysLER Estimate Connection StateFddi Port Status Color Codes Chassis Manager WindowDevice Type Viewing Hardware TypesModule Type Module Type Window Viewing I/F Summary InformationDescription IndexSta Interface Performance Statistics/Bar GraphsLoad Raw CountsInterface Statistics Window RateAddress ErrorUnicast Non-UnicastPackets Received Received only Using the Find Source Address FeatureTransmit Queue Size Transmit only Packets Transmitted Transmit onlyManaging the Hub Setting the Device Date and TimeBridge Ports Enabling and Disabling PortsModule Ports ATM Configuration Accessing the ATM Connections WindowConnection Data ATM ConfigurationVPI SettingsAdding a New Connection Configuring ConnectionsDeleting a Connection ATM Configuration Configuring Connections Fddi Management Fddi Management ConfigurationMAC State Req. Requested Target Token Rotation Time SMT VersionNeg. Negotiated Concentrator Non-M Ports Concentrator M PortsNumber of MACs MAC PathConnection Policy 15 32,768 a permanently set value for this bit Station List Address ModeNumber of Nodes Node Class Stations PanelTopology Upstream NeighborPerformance Transmit Frames Frame ErrorsReceive Frames Lost FramesFddi Management Performance Bridging Bridging Bridge Status WindowBridge State on Interface Up TimeInterface Type Bridge AddressConfiguring Duplex Modes Enabling and Disabling Bridging Performance Graphs Bridge StatisticsForwarded Green Filtered Magenta Total Errors RedXmitted Blue Configuring the Bridge Performance GraphsForwarded ErrorsFiltered XmittedForwarded to Interface Statistics WindowForwarded from Description Using Source Addressing Port Source Addresses Window Setting the Ageing TimeBridge Spanning Tree Bridge Priority Configuring the Bridge Spanning Tree WindowRoot Cost Root BridgeRoot Port ProtocolHello Time Forwarding DelayMax Age Hold TimeChanging Bridge Spanning Tree Parameters Changing the Spanning Tree Algorithm Protocol Type Changing Bridge PriorityChanging Hello Time Changing Max Age Time Changing Forwarding Delay TimeChanging Port Priority Changing Path Cost Filtering DatabaseBridging Bridging Number ListCapacity Ageing TimeReceive Port Configuring the Filtering DatabasePort Filtering Changing the Type of Entry Altering the Ageing TimeChanging the Receive Port Changing the Port Filtering ActionClearing All Permanent, Static, or Dynamic Entries Bridging Filtering Database Index Index-2 Index-3 Index Index-4