Enterasys IRM2, User Manual

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Accessing the Alarm Limits Windows 5-5
Alarm Limits
packets were collisions (15 collisions for every good packet). Therefore, the lower
you set your threshold value, the lower the percentage of collisions per good
packet you are allowing.
Remember, a repeater-level alarm will calculate the number of collisions per good
packet based on all traffic received on the repeater channel; a board- or port-level
alarm will make the calculation based on traffic on the specific board or port only.
Packets
Use the text box in this field to determine the number of good packets (excluding
all errors) that must be processed by the repeater, board, or port within the
user-specified time before an alarm is triggered. Allowable values are 1 to Ý 4
billion (2
32
-1).
Broadcast Packets
Use the text box in this field to determine the number of broadcast packets that
must be processed by the repeater, board, or port within the user-specified time
before an alarm limit is reached. Allowable values are 1 to Ý 4 billion (2
32
-1).
% Errors of Type
Use the text box in this field to determine what percentage of packets received by
the repeater, board, or port within the specified time interval can be errors of the
selected type or types before an alarm is triggered. Allowable values are 1 to 100;
percentages will be calculated based on the number of error packets of all types
selected (all those with an X in their check box). Again, a repeater-level alarm will
count all selected error types received by the repeater; a board- or port-level alarm
will count all selected error types received by the individual board or port.
You can select any combination of the following error types:
CRC Errors If this check box is selected, all packets with
Cyclical Redundancy Check (CRC) errors will be
included in calculating the overall percentage of
errors.
Framing Errors If this check box is selected, all misaligned
packets will be included in calculating the
overall percentage of errors. A misaligned packet
is one with a non-integral number of bytes; these
are also sometimes referred to as alignment
errors.
Runts If this check box is selected, the number of runt
packets will be included in calculating the
overall percentage of errors. A runt packet is one
that is less than the minimum Ethernet frame
size of 64 bytes.