Re: "net arp" command displays "ARP cache is empty" even after a series of arpings from peer devices #nrf52840

Jukka Rissanen


from the attached .config file, the zephyr IP address is, and if you ping it from your network, you get a ICMP reply correctly but still no entry in arp cache in zephyr, is this correct? There definitely should be entry in arp cache as otherwise zephyr would not be able to send the reply back. Are you sure that you are pinging the correct device in this case?


On Fri, 2019-05-31 at 04:00 -0700, giriprasad@... wrote:

I have interfaced "ENC28J60" to "PCA10056"(NRF52840) through SPI. Made necessary configurations in order to reflect hardware changes in software. Flashed sample application, "dumb_http_server" to the board. Enabled "ARP" and "ICMP". I am able to ping the board from peer devices in network and vice versa. Also, I am able to "arping" the board from peer devices in network. After this, I have issued "net arp" command in the serial console of the board. By this, I am expecting a list of peer devices to be displayed on the console. But console throws a message saying "ARP cache is empty". Can I know the reason for this behavior? Please let me know, if I was wrong in the process. Also, let me know if more information is needed. Attached configuration file for reference.

Thanks & Regards,
Giri Prasad N.

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