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Serial link max Load

Hi, anybody knows what the recommendation for maximum serial link utilizations (70%, 80% xx? )?

More than this value the router will drop packets ?

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Re: Serial link max Load


actually the router can drop packets even with much less traffic than 70%. Suppose a burts of traffic happens, you will have drops, then low traffic again. But of course, the higher the average traffic volume, the higher the probability of drops.

What is tolerable or reccomendable depends on the criticalness of the application, and the cost of the next circuit upgrade.

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Re: Serial link max Load

Hi, Pls Rate / Vote if Helps

I can recommend you this way, it depends on the "Bandwidth" definition in the Serial Interface.

Second case, Check the show buffers notifications (if any).NOTE: The term 'Failures (in logs)' in the huge buffers tracks the number of packets that

were dropped due to unsuccessful attempts to allocate a buffer. This can occur in spite of (or even because of) the router's attempts to create additional free

buffers when their number declines below minimum. TRY THIS: Use the 'show memory' command to check the amount of free memory.

CAUTION: Care, expertise, and follow-up monitoring are necessary if system buffers

need to be adjusted. Incorrect adjustments can severely affect hardware and network


Third Case, Check the show controllers serial notifications (if any).These counters increment when the data that comes into the interface is very high,and the router is unable to fill the hardware buffers. In such a scenario, some packet drops can occur. There is no cause for concern if the values of these error counters increment very slowly. Some amount of buffer errors is normal and does not affect the interface operation. However, if the counter values increment very fast, tune the buffers for better performance. Paste the output of the show buffers command to the Output Interpreter in order to tune the recommended buffers and corresponding buffer values.

PLS Rate / Vote if Helps

Best Regards,

Guru Prasad R