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Router 2811 Ping Responses


We received this question from our CSC Facebook community.


i  have a question that router 2811 having ping responses 2000ms on  directly connected devices.whats the reason behind this and one thing is  also that in cpu processing NAT Translations are too high.please  suggest if any of you have a exact idea about this
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Re: Router 2811 Ping Responses

There is not much information to work with here but we will do our best to provide some helpful answers.

There are a couple of things that could be involved in the slow ping times and some of them would be on the 2811 and some would be beyond the 2811. Here are some possibilities:

- is it possible that there is a duplex mismatch on the interface? If one device is running full duplex and the other device is running half duplex this will result in dropping packets causing retransmissions and impacting latency on the interface.

- is it possible that the interface is very busy with other traffic and that the pings are slowed by this?

- is it possible that there is a QOS configuration (Quality of Service) which is controlling traffic through the interface and in particular is there possibly any bandwidth shaping specified which would result in delaying some traffic?

- since the ping response time is the sum of the time to transmit the request, the time to transmit the response, and the time of the other device to process (to receive the request, pass the request up the stack, recognize and process the request, formulate a response, prepare the response from transmission, pass the response down the stack) is it possible that the other device is treating the ping as a low priority task and is slow to respond?

As to the issues with NAT it would be helpful is we knew some details including how much traffic is being sent through this 2811? Of that traffic how much is being translated? How many translations are being performed? How many are static translations, how many are dynamic translations? are the dynamic translations using address pools or are they overload/PAT translations?