o  alignment error

    This event is generated whenever an incoming frame does not
    contain an integral number of octets. This error can be caused
    by several conditions, such as electromagnetic interference, late
    collisions, or improperly set hardware parameters (for example,
    receiver squelch).

 o  carrier check failure

    This event is generated on a transmission that failed, either
    because the data link did not sense the receive carrier signal
    that must accompany transmission of a frame, or because the data
    link did not detect an error. This error indicates a failure
    in either the transmitting or receiving hardware, such as the
    transceiver or transceiver cable.

 o  data overrun

    This event is generated whenever an incoming frame is lost
    because of a hardware resource failure such as insufficient
    hardware buffers or insufficient CPU time.

 o  excessive collision

    This event is generated whenever a transmission fails because the
    medium access algorithm reached the maximum number of allowable
    retransmission attempts resulting from collisions. This error can
    occur when too many systems are trying to transmit at the same
    time or when there are cable problems.

 o  frame check error

    This event is generated whenever an incoming frame fails
    the Frame Check Sequence test. This error can be caused by
    several conditions, such as electromagnetic interference, late
    collisions, or improperly set hardware parameters (for example,
    receiver squelch).

 o  frame too long

    This event is generated whenever a remote system sends a frame
    that exceeds the CSMA/CD MAC maximum length.

 o  late collision

    This event is generated whenever a transmission fails because a
    collision was detected after the allowed window for collisions
    had elapsed. This error indicates either a problem with another
    system's carrier sense or a weak local transmitter.

 o  receive data length error

    This event is generated whenever a remote system sends an 802.3
    frame having a length field value that is not valid for the
    number of octets actually received by the MAC.

 o  unavailable station buffer

    This event is generated whenever an incoming frame is discarded
    because there is no station buffer available to receive it. This
    error indicates a lack of local station buffers; that is, a lack
    of buffers between the cable and the user buffers.

    On OpenVMS, this event is blocked by default.  If you wish to
    unblock this event, you may do so using the NET$EVENT_LOCAL
    script.  For more information about that script, refer to
    HELP NETWORK_MANAGEMENT EVENT_DISPATCHER.

 o  unavailable user buffer

    This event is generated whenever an incoming frame is discarded
    because there is no user buffer queued to the appropriate port
    to receive it. This error indicates a lack of buffers in the
    user process; that is, the buffers supplied by the user for the
    Receive function.

    This event is one that network managers commonly select to be
    blocked.  If you wish to block this event, you may do so using
    the NET$EVENT_LOCAL script.  For more information about that
    script, refer to HELP NETWORK_MANAGEMENT EVENT_DISPATCHER.

 o  unrecognized individual destination pdu

    This event is generated whenever an incoming frame that matches
    an enabled individual MAC address is discarded because the frame
    does not satisfy the filter criteria of any port. This error
    indicates that a remote system is using a protocol that is
    locally unsupported or that the local system has not enabled a
    protocol type, protocol identifier, or LLC SAP address that it
    should have.

 o  unrecognized multicast destination pdu

    This event is generated whenever an incoming frame that matches
    an enabled multicast MAC address is discarded because the frame
    does not satisfy the filter criteria of any port. This error
    indicates that the local system has not enabled an Ethernet
    protocol type, SNAP identifier, or LLC SAP address that it should
    have, or that a remote system is sending traffic that is invalid
    for the combination of multicast and the currently specified
    protocol type, SNAP identifier, or LLC SAP.

    On OpenVMS, this event is blocked by default.  If you wish to
    unblock this event, you may do so using the NET$EVENT_LOCAL
    script.  For more information about that script, refer to
    HELP NETWORK_MANAGEMENT EVENT_DISPATCHER.