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My application is testing devices connectivity using ping ICMP functionality. It is working fine for all devices except for a particular device that is CISCO wireless controller. I am not able to ping the device.

I am able to ping the device through command prompt, but when I debug my application I found that I am able to send ping but not able to receive from the device. After doing further analysis I found that select() function is returning 0.

Also I have got Wireshark captures and found that the packets I am sending have correct ICMP checksums but the ICMP echo reply packets have incorrect checksum. It seems due to the packets being discarded.

Please suggest how to resolve the issue and also is there any way to disable ICMP checksum check.

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You will have to give us infinitely more information. What Operating System is this application running on? What model of Cisco device is it? –  Nic Young Mar 2 '12 at 6:30
@NicYoung: The cisco device is Cisco Wireless Controller AIR-CT5508-250-K9. The application is running on windows 2008. FYI my application is able to ping all other devices. Also the device is pingable through command prompt and the echo reply packets arrived are having correct checksum. –  patthar Mar 2 '12 at 6:53
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