Re: No ARP Table, and a DNS issue.

On 3.7.10 9:31 , jny0 wrote:
I have an (embedded) linux device which is trying to communicate with
a URL (e.g. When I wireshark the output
from the eth0, all I see is an ARP request for the default gateway,
which is never resolved. When I view the ARP table (arp, arp
neighbor, etc), Linux tells me it doesn't recognise the command.

This means that the default gateway is not in the same physical
local network as your device, or your device is banned by the gateway.

Please note that in a network built of multiple local networks,
the default gateway is different in each local network. It is
the device connected to both the local network and to next
network towards the Internet.

This may be related, or may not. If I ty to ping an IP address, it
works fine. If I try to ping the URL associated with the IP address,
it doesn't. Sounds like a DNS problem. So, I checked /etc/
resolve.conf, but this is fine.

You do not get a connection to the DNS server, maybe of the
same problem as above.

Other machines (admittedly, no embedded), don't have these problems.
Kernel was build using buildroot, and busybox, on a Fedora Linux

If you still have problems, please post the layout of
your network and the addresses, gateways and netmasks
assigned to each node.


Tauno Voipio
tauno voipio (at) iki fi


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