| Estimated link error rate is the measured (approximate) bit error rate inbound
on that port, expressed logarithmically. In other words, "9" means 10^-9.
The standard calls for link error rate of 10^-10 or better, so this number
should be at least 10. (It takes a while to measure link error rates like
that, so don't expect a meaninful number seconds after startup!) If you see
this number dropping, you should investigate what's happening to the link.
If the number goes below 8, the link will be disconnected ("LEM reject").
"LEM error rate" -- there is no counter by that name in the spec. Do you
mean "Link errors"? (If not, it may be a misnamed version of the counter
above.) If it's "link errors" then that's simply a count of the individual
bit errors seen inbound on that port. The Estimated link error rate measures
the average rate of these events; the Link errors counter simply counts them.
In normal operation, it is acceptable to see this counter go up slowly,
since it is acceptable to have some bit errors. But the error rate is supposed
to be no higher than 10^-10 (and on a correctly constructed link should be
significantly better, e.g., 10^-12), so this counter should count quite slowly.
paul
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