Arp request 0 responses

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I'm trying to ping my android device (10.0.0.38) from my PC (10.0.0.56). They both are in the same network.

However, when I use arping to send ARP requests from my PC to my Android, I don't receive any responses.

Network capture: Who has 10.0.0.38 timeouts

This is ofcourse the same when I ping because that also needs ARP to resolve.

The only way for me to solve this is by manually adding entries in the ARP table from both my PC and Android.

Why do I have to do this to make ARP requests work?
Is there another solution?

EDIT : I am editing this question because there is more infos now. So I didn't tell first that this problem was ocurring at my office. What I realized is that late afternoon, when almost everyone left the office, it worked without having to add new entries in the arp table.
So I'm guessing the problem comes from something blocking arp requests in the network, but what could it be ?
This is a screenshot of when it worked again :

Network Capture: arp requests sent and replied

Nabil B.

Posted 2016-07-11T14:01:12.833

Reputation: 76

I tried pinging another device (10.0.0.11) from my PC and this is the same problem, Destination Host Unreachable. – Nabil B. – 2016-07-11T14:40:03.417

If you can ping others devices from other devices, but only the PC actus up when pinging all other then you have identified the weird machine, Namely the PC. (and vice versa with other device(s)). – Hennes – 2016-07-11T16:59:50.200

Uhm, just saw http://storage1.static.itmages.com/i/16/0711/h_1468252998_9471790_bc9b6feaaa.png. That means .38 is not replying. Weird. I can think of no sane firewall rule which does that. Anyway, editing that into the post.

– Hennes – 2016-07-11T17:00:59.543

One more idea: what is the network mask on the android device. Are both on 10.0.0.0/24 ? If that is different it might not recognise a broadcast as a broadcast. – Hennes – 2016-07-11T17:06:22.060

Thanks for editing. Yes they have the same broadcast and mask, which is 10.0.0.255 and 255.255.255.0 – Nabil B. – 2016-07-12T08:52:22.503

Answers

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As I have mentioned in your previous post, the most possible cause of this issue is the ARP firewall on the android device.

If you want to find the route cause of this issue, you need to perform a network capture on the device with this issue. I'm not sure if the android device supports network capture. So my suggestion is start with the PC side.

First, install a network capture software such as wireshark, network monitor. Configure the filter to match the ARP message with the source MAC of the android device so that you are able to find the useful information from thousands of packets.

Then start the capture first and immediately start pinging PC from android side.

When the error message shows, stop the capture.

If the PC doesn't receive any ARP request from android or the PC receives and reply the ARP request from android, it means that there is something on the network blocks the ARP message.

If the PC receives the ARP message but doesn't reply it, it means that the ARP is filtered by the PC's firewall or the PC is configured to not reply a ARP message.

There are too many possibilities, all you need is learning how ARP works and find some tools to find the difference with the normal ARP process and then find the root cause yourself.

Steven Lee - MSFT

Posted 2016-07-11T14:01:12.833

Reputation: 855

I think this is the first problem. I did not tell in my question that I'm having this problem at my office. Now that almost everyone is gone, the arp requests are sent and replied, earlier today, my wireshark capture looked like this : http://storage1.static.itmages.com/i/16/0711/h_1468252998_9471790_bc9b6feaaa.png and now it looks like this : http://storage4.static.itmages.com/i/16/0711/h_1468256051_9865967_545de92e2d.png So what could be blocking the arp requests when everyone is in the office ?

– Nabil B. – 2016-07-11T16:52:23.623

@NabilB. - You should update your question. – Ramhound – 2016-07-11T17:00:38.943

Ok, I edited it. – Nabil B. – 2016-07-12T08:33:52.960

@NabilB. I've seen a lot of unanswered ARP request in your first picture. If you capture the packets on the source side, it's meaningless. Because you only know that the source has sent the request. We can't find any information about who drops the request. We need perform a capture on the destination side. According to the picture, you are pinging android device from PC and capturing the packets on the PC. – Steven Lee - MSFT – 2016-07-12T15:51:32.083

Asked: 2016-07-11T14:01:12.833

Viewed: 724 times

Active: 2016-07-12T08:33:26.473