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New Member

Slow Ping Times... Your opinion!

I am having unusually slow ping times at various times thru a wireless LWAPP network. I can be right next to (20 feet) away and ping times can vary 10-20ms. Occasionally they may go higher and I may lose a packet occasionally. On Autonomous Wireless networks I have designed this has never been an issue in any wireless network (40+). I am new to LWAPP/Controllers so I am not sure what to expect. I have read the notes for the 4.0.179 code on the controllers and found this:

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Pinging from a Network Device to a Controller Dynamic Interface Pinging from a network device to a controller dynamic interface may not work in some configurations.

When pinging does operate successfully, the controller places Internet Control Message Protocol(ICMP) traffic in a low-priority queue, and the reply to ping is on best effort. Pinging does not pose a

security threat to the network. The controller rate limits any traffic to the CPU, and flooding the controller is prevented. Clients on the WLAN associated with the interface pass traffic normally.

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Would this statement hold true of general pings from the wireless network thru the network to let's say a router on the wired network?

I rely heavily on pings to test layer 3 mobility and WLAN connectivity. Any ideas how to better test this?

2 REPLIES
New Member

Re: Slow Ping Times... Your opinion!

This only holds true to pinging the controller, therefore the statement "limits traffic to the CPU". Traffic to other network devices does not go through CPU, so it is unaffected.

RF is a shared medium, and each site is different form the last. Also remember that LWAPP APs can change channels, and also briefly go off-channel to scan for rogues, noise, interference, etc... but retransmissions should take care of that. Long answer short, without a wireless sniffer, there's no confirming where your packets are going.

New Member

Re: Slow Ping Times... Your opinion!

Thanks for the reply. However, I am happy to report that we fixed the issue. The issue turned out to be a bad SUP in a 6509 that was routing for the network. It took awhile but one of our guys traced down that the SUP was dropping packets. Swapped and now all packets are 1-2ms.

Thanks for the reply...!

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