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Viewing statistics

Device Manager gathers Ethernet statistics that you can have graphed in a variety of formats, or you can save them to a file and export the statistics to an outside presentation or graphing application.

To view RMON Ethernet statistics:

  1. Select an object (port or chassis).
  2. Do one of the following:
  3. Click the RMON tab.
  4. The RMON tab opens and displays the Ethernet statistics.


    Field Description
    Octets
    The total number of octets of data (including those in bad packets) received on the network (excluding framing bits but including FCS octets). You can use this object as a reasonable estimate of Ethernet utilization. For greater precision, sample the etherStatsPkts and etherStatsOctets objects before and after a common interval.
    Pkts
    The total number of packets (including bad packets, broadcast packets, and multicast packets) received.
    BroadcastPkts
    The total number of good packets received that were directed to the broadcast address. Note that this does not include multicast packets.
    MulticastPkts
    The total number of good packets received that were directed to a multicast address. Note that this number does not include packets directed to the broadcast address.
    CRCAlignErrors
    The total number of packets received that had a length (excluding framing bits, but including FCS octets) of between 64 and 1518 octets, inclusive, but had either a bad Frame Check Sequence (FCS) with an integral number of octets (FCS Error) or a bad FCS with a nonintegral number of octets (Alignment Error).
    UndersizePkts
    The total number of packets received that were less than 64 octets long (excluding framing bits but including FCS octets) and were otherwise well formed.
    OversizePkts
    The total number of packets received that were longer than 1518 octets (excluding framing bits but including FCS octets) and were otherwise well formed.
    Fragments
    The total number of packets received that were less than 64 octets in length (excluding framing bits but including FCS octets) and had either a bad Frame Check Sequence (FCS) with an integral number of octets (FCS Error) or a bad FCS with a nonintegral number of octets (Alignment Error). It is entirely normal for etherStatsFragments to increment because it counts both runts (which are normal occurrences due to collisions) and noise hits.
    Collisions
    The best estimate of the total number of collisions on this Ethernet segment.
    Jabbers
    The total number of packets received that were longer than 1518 octets (excluding framing bits, but including FCS octets), and had either a bad Frame Check Sequence (FCS) with an integral number of octets (FCS Error) or a bad FCS with a non-integral number of octets (Alignment Error). Jabber is defined as the condition where any packet exceeds 20 ms. The allowed range to detect jabber is between 20 ms and 150 ms.
    <=64
    The total number of packets (including bad packets) received that were less than or equal to 64 octets in length (excluding framing bits but including FCS octets).
    >64
    The total number of packets (including bad packets) received that were greater than 64 octets in length (excluding framing bits but including FCS octets).
    >127
    The total number of packets (including bad packets) received that were greater than 127 octets in length (excluding framing bits but including FCS octets).
    >255
    The total number of packets (including bad packets) received that were greater than 255 octets in length (excluding framing bits but including FCSoctets).
    >511
    The total number of packets (including bad packets) received that were greater than 511 octets in length (excluding framing bits but including FCS octets).
    >1023
    The total number of packets (including bad packets) received that were greater than 1023 octets in length (excluding framing bits but including FCS octets).


    Statistic Description
    Absolute
    The total count since the last time counters were reset. A system reboot resets all counters.
    Cumulative
    The total count since the statistics tab was first opened. The elapsed time for the cumulative counter is shown at the bottom of the graph window.
    Average/sec
    The cumulative count divided by the cumulative elapsed time.
    Min/sec
    The minimum average for the counter for a given polling interval over the cumulative elapsed time.
    Max/sec
    The maximum average for the counter for a given polling interval over the cumulative elapsed time.
    Last/sec
    The average for the counter over the last polling interval.

See also


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