Enterasys Networks MicroMMAC-T Lost Frames, Congestion Errors, Token Errors, Frequency Errors

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Token Ring Statistics

Lost Frames

Displays the number of lost frame errors detected on the ring. These occur when a station is transmitting and its TRR (Timer, Return to Repeat) timer expires. This timer ensures that the station returns to the data repeat state.

Lost frames are usually caused by a station entering or leaving the ring as the frame is circulating – since this often throws the ring temporarily out of synchronization. Lost frames will cause the active monitor to initiate the ring purge process and issue a new token.

Congestion Errors

Displays the total number of error conditions when a ring station recognizes a frame addressed to it, but has no available buffer space; that is, the station is receiving frames faster than its adapter can copy information from the buffers. This indicates that the station is congested.

F.C. Errors

Displays the count of frame copied (FC) errors detected on the ring. These are recorded when the management station recognizes a frame addressed to it and detects that the Frame Status field’s Address bits are set to 1, indicating a possible line surge or duplicate address.

Note that it is virtually impossible to have a ring with duplicate addresses, since most of the time the ring uses the hard-coded address on the adapter, and duplicate addresses are checked for when a station inserts itself into the ring. However, a system administrator can pass a locally assigned address to the adapter, so it is possible to unintentionally administer a duplicate address while a device is on the ring. This error is more commonly caused by transparent bridging on a token ring network.

Token Errors

Displays the number of token errors detected on the ring. These occur when the management station, as the active monitor, recognizes an error condition that needs a token transmitted. This occurs when the TVX (Timer, Valid Transmission) timer expires. This timer records the time in which a valid transmission can occur.

As in lost frames, the major cause for token errors is the disruption of the ring as stations enter or leave the ring. Note that token errors are only reported by an active monitor. If you see a token error reported by another station, it was serving as active monitor at some previous time.

Frequency Errors

A frequency error occurs when the ring clock frequency and the station’s internal crystal clock frequency differ by an excessive amount. This type of error happens more often on 16 Mbps rings than on 4 Mbps rings; it can also be a symptom of too many stations on the ring.

Detection of a frequency error initiates the monitor contention process, since this typically indicates that the active monitor is not present or is malfunctioning.

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Network Level Statistics

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Contents MicroMMAC-T Users Guide Page Virus Disclaimer Page Restricted Rights Notice Page Contents Contents Chapter Token Ring StatisticsChapter Station List and Station Map Chapter Token Ring AlarmsIndex Contents Viii Introduction Using This Guide IntroductionRelated Manuals Using the MouseSoftware Conventions Left Mouse Button Right Mouse Button Using Window Buttons Common MicroMMAC-T Window FieldsDevice Name IP AddressLocation MAC AddressGetting Help Using On-line HelpGetting Help from Enterasys Global Call Center Introduction MicroMMAC-T Chassis View Viewing Chassis Information Front Panel Information Time Menu StructureDate MicroMMAC-T Chassis View Menu Structure Device MenuPort Status Menu Network Menu Utilities MenuModule Menus Help MenuPort Menus Ring Port Menus Port Status DisplaysSelecting a Port Status View Load ErrorsStatus Ring Port Status Port AssignmentPort Status Color Codes Viewing Hardware Types Chassis Manager WindowClick on MIBs Supported Device Type Managing the HubModule Type Management Station Configuration Accessing the TR Management Station Configuration WindowSetting Station Name and Location Station Name Configuration WindowHost Error Report Timer Delay Enable Beacon RecoverySpecifying Ring Management Functions Inhibit Active MonitorEnable Ring Poll Recovery Viewing Network Information Selecting the RingNetwork Information Window Fields Ring of X Configured Rings Viewing Module StatusToken Ring Board Status Window Fields Board NumberAccessing the Ring Port Status window Viewing Ring Port StatusLast Wire Fault Ring Port Status Window FieldsPort Media TypeSetting the Device Date and Time Using the Media Type and Phantom Current Radio ButtonsUsing an Uninterruptable Power Supply UPS 13. Device Date Change WindowAccessing the UPS Window 14. The UPS WindowBattery Output Battery CapacityUPS Uptime Line VoltageResetting the Device Setting the UPS IDUsing the Test Option Using the Disconnect OptionEnabling and Disabling Port Mapping Enabling and Disabling Link Traps 15. The Port Map WindowSetting Token Ring Boards to Automode Enabling and Disabling Link Traps at the Board LevelEnabling and Disabling Station Ports Enabling and Disabling PortsEnabling and Disabling Ring Ports Ring Out Enable/Disable Viewing I/F Summary InformationIndex TypeDescription Physical StatusInterface Performance Statistics/Bar Graphs Raw CountsRate Viewing Interface DetailAddress UnicastMaking Sense of Detail Statistics Transmitted Errors /Packets Transmitted Statistics Window Features Setting Total, Delta, or Cumulative CountsViewing Elapsed, Average, and Peak Activity Levels Token Ring StatisticsSetting the Statistics Poll Interval New Timer Interval Text BoxAccessing the Network Statistics Selections Network Level StatisticsNetwork Statistics Window General Information Fields Ring Speed Ring Status Fields Stations Inserted Active MonitorSoft Error Fields Beacon StatisticsInternal Errors Burst ErrorsAbort Sequences Congestion Errors Token ErrorsFrequency Errors Lost FramesTotal Errors Network Timer StatisticsNetwork Timer Statistics Window Fields Frames Network Performance GraphsKBytes Configuring the Network Performance Graph Network Performance Graph StatisticsNetwork Events Red Traffic BlueFrame Size Window Total and Delta Graph DisplayUsing the Pie and Bar Radio Buttons Frame Sizes Window with Pie ChartProtocol Statistics Window Accessing the Management Station Statistics Selection Management Station StatisticsSoft Errors Fields FC Errors Soft ErrorsHard Errors Fields Signals LostRecoveries Lobe Wire FaultHard Errors Transmitted BeaconsPort Level Statistics Accessing the Station Port MenuStation Statistics Window Station Statistics Window General Fields Station NameLink Time Station Statistics Window Performance FieldsStation Statistics Window Soft Error Fields Station Timer Statistics Window Station Timer Statistics Window Fields Port Performance GraphsTotal Errors Red Port Performance Graph StatisticsConfiguring the Port Performance Graph Token Ring Statistics Token Ring Alarms Ring-Level Alarm LimitsAccessing the Alarm Limits Window Ring-Level Alarm Limits for Network EventsRing-Level Station Alarms Token ErrorsSetting Ring-Level Alarm Limits LineStation-Level Alarm Limits Accessing the Station Alarm Limits Window from the Port MenuToken Ring Alarms Setting Station-Level Alarm Limits Station Alarm Limits WindowToken Ring Alarms Station List and Station Map Station List WindowAddress Mode Station List Window FieldsGeneral Fields Number of Nodes/StationsViewing Station Statistics Station FieldsSetting Station Alarms Viewing Station Timer StatisticsRemoving a Station from the Ring Viewing the Station Port Performance Graph Using the MAC/Canonical ButtonPrinting the Station List Resetting Counters Station MapStation Map Window Fields Number of NodesViewing the Station Map Station Pop-up Text BoxesStation Map with Text Boxes Node AddressStation Command Menu Manipulating the Station Map Magnifying a Portion of the MapRotating the Station Map Resizing the Station Map Window Station List and Station Map Symbols IndexIndex-2 Index-3 Index-4
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