ARP table woes prevent reliable networking on LAN

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What steps will reproduce the problem?
1. connect Glass to a LAN with WiFi
2. ping Glass from a PC or ping the PC from Glass (with adb) 

What is the expected output? What do you see instead?
Pinging Glass (or pinging from Glass) sporadically fails. Any software talking 
from or to Glass on the LAN with TCP also fails at this point. This does not 
happen all the time, but enough to make networking on the LAN useless. 

The issue seems to be related to the ARP table in Glass. Here is the output of 
trying to ping a PC from Glass (with adb) and then showing the ARP tables:

1|shell@android:/ $ ping 192.168.2.10                                          
PING 192.168.2.10 (192.168.2.10) 56(84) bytes of data.
From 192.168.2.11 icmp_seq=1 Destination Host Unreachable
From 192.168.2.11 icmp_seq=2 Destination Host Unreachable
From 192.168.2.11 icmp_seq=3 Destination Host Unreachable
^C
--- 192.168.2.10 ping statistics ---
4 packets transmitted, 0 received, +3 errors, 100% packet loss, time 3013ms
, pipe 3
1|shell@android:/ $ ip neighbor show
fe80::222:75ff:fe5f:9430 dev wlan0 lladdr 00:22:75:5f:94:30 router STALE
192.168.2.1 dev wlan0 lladdr 00:22:75:5f:94:30 REACHABLE
192.168.2.10 dev wlan0  FAILED

Other devices are able to ping 192.168.2.10, but Glass cannot do so because of 
this ARP issue. 

What version of the product are you using? On what operating system?
I've tried this on two units of Glass, one v1 and the other v2, and both have 
the same defect.

Please provide any additional information below.
I've tested the issue with several different routers, so that doesn't seem to 
be the issue. Setting static ARP entries solves the problem, but is not a real 
solution (too complicated for users).

To debug a bit further, while being affected by the issue, I tried to connect 
Glass to a PC on the LAN (Glass was the client, the PC the server) while 
running wireshark.

Wireshark does not see any 'who has' ARP requests coming from Glass. While 
trying to make the connection, the ARP table shows the state as INCOMPLETE, 
shortly after which it changes to FAILED:

shell@android:/ $ ip neighbor show                                             
fe80::222:75ff:fe5f:9430 dev wlan0 lladdr 00:22:75:5f:94:30 router STALE
192.168.2.1 dev wlan0 lladdr 00:22:75:5f:94:30 REACHABLE
192.168.2.10 dev wlan0  INCOMPLETE
shell@android:/ $ ip neighbor show                                             
fe80::222:75ff:fe5f:9430 dev wlan0 lladdr 00:22:75:5f:94:30 router STALE
192.168.2.1 dev wlan0 lladdr 00:22:75:5f:94:30 REACHABLE
192.168.2.10 dev wlan0  FAILED

Sometimes, pinging Glass from the computer seems to fix the ARP table, but this 
is not always the case. When it does work, this is what the ARP entry states 
look like: 

shell@android:/ $ ip neighbor show                                             
fe80::222:75ff:fe5f:9430 dev wlan0 lladdr 00:22:75:5f:94:30 router STALE
192.168.2.1 dev wlan0 lladdr 00:22:75:5f:94:30 STALE
192.168.2.10 dev wlan0 lladdr d0:df:9a:28:3c:d4 DELAY
shell@android:/ $ ip neighbor show                                             
fe80::222:75ff:fe5f:9430 dev wlan0 lladdr 00:22:75:5f:94:30 router STALE
192.168.2.1 dev wlan0 lladdr 00:22:75:5f:94:30 STALE
192.168.2.10 dev wlan0 lladdr d0:df:9a:28:3c:d4 REACHABLE

Original issue reported on code.google.com by andresac...@gmail.com on 2 Feb 2014 at 2:45

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Original comment by ala...@google.com on 3 Feb 2014 at 5:22

• Changed state: Accepted
• Added labels: Component-Other-API, log-12872300

[GoogleCodeExporter]

Hello:

I have a similar problem. I am able to ping from PC to glass, but ping from 
glass to PC fails (although pings from glass to gateway works). 

"ip neighbor show" output looks good and is consistent with what the entries 
should like.

Everything else, like routes look good. Any ideas?

Thanks,

Original comment by harsha.h...@gmail.com on 9 Jun 2014 at 3:13