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I have an Open Mesh access point connected to the same router (an Aerohive BR100) than an Axis camera. I would like to automate the discovery of the camera's IP from inside the Open Mesh sensor, knowing the camera's MAC address.

This bad Ascii art shows how the things are cabled:

+================= Aerohive router ================+
|    ____    ____    ____    ____          ____    |
|    [..]    [..]    [..]    [..]          [..]    |
      ||      ||              ||            ||
     Axis   OpenMesh     borrajax-pc        DSL
    camera  access pt.   (my laptop)     connection

The router where camera and OpenMesh devices are connected to assigns IP addresses in the shape: 10.200.255.XXX/24

If I unplug my laptop (borrajax-pc) from the Aerohive router and connect it to the WiFi network provided by the Open Mesh sensor, my IP becomes (which is ok, since it is an IP provided by the Open Mesh sensor, and that's my router/gateway... my boss, after all). Anyhow... at this point, I can ssh into the sensor itself (as I said it's my gateway):

borrajax@borrajax-pc:~$ ssh root@
root@'s password: 

BusyBox v1.19.4 (2013-01-08 11:35:01 UTC) built-in shell (ash)
Enter 'help' for a list of built-in commands.

  _______                          ________             __
 |       |.-----.-----.-----.  _  |        |.-----.----|  |__
 |   -   ||  _  |  -__|     | |_| |  |  |  ||  -__|__--|     |
 |_______||   __|_____|__|__|     |__|__|__||_____|____|__|__|
          |__| ---------------------
 (c) Open-Mesh, Inc. All rights reserved.
 firmware-ng: fw-ng-r443
 Powered by these open source projects:

But when I'm inside the sensor, none of its interfaces have an address like the ones the external Aerohive router is providing (10.200.255.XXX/24), so I can't see my neighbors in one hop (or jump).

Just in case it's helpful, here's a list of interfaces with its assigned IP address:

root@BorrajaX_Test_Sensor:~# ifconfig
bat0.2     inet addr:  Bcast:  Mask:
br-lan2    inet addr:  Bcast:  Mask:
br-meship  inet addr:  Bcast:  Mask:
br-priv    inet addr:  Bcast:  Mask:
br-pub     inet addr:  Bcast:  Mask:
lo         inet addr:  Mask:

As you can see, none of the IPs looks like the ones provided by my router (10.200.255.XXX)

Now, if I find the camera's IP through other ways, and I find out said IP is, for instance, this is what happens within the sensor.

root@BorrajaX_Test_Sensor:~# traceroute
traceroute to (, 30 hops max, 38 byte packets
 1 (  2.265 ms  0.608 ms  1.378 ms
 2 (  3.227 ms  1.265 ms  1.092 ms

So it hops through the br-lan2 interface and "sees" it properly. I can even ping it.

root@BorrajaX_Test_Sensor:~# ping
PING ( 56 data bytes
64 bytes from seq=0 ttl=63 time=2.788 ms

But the ARP table doesn't register the mapping MAC <--> (I'm guessing because it's jumping once through

Is there any way of arping a "neighbor" when that neighbor is connected to the same router than the Open-Mesh device itself? Also, as I mentioned, the IP the Aerohive router assigns to the Open-Mesh device seems to become hidden somehow inside the Open-Mesh device. Is there any way of overcome this "hidden-ness"?

PS: If I do the whole thing from my laptop, it works fine:

1st: Verify that my IP belongs to the range assigned by my router (10.200.255.XXX)

borrajax@borrajax-pc:~$ ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 5c:f9:dd:52:10:78  
          inet addr:  Bcast:  Mask:    
          [ . . . ]

2nd: Check the arp table:

borrajax@borrajax-pc:~$ arp -n
Address                  HWtype  HWaddress           Flags Mask            Iface           ether   e0:1c:41:30:ea:40   C                     eth0

No camera!!

3rd: fping to the whole 10.200.255.XXX subnetwork:

fping -g is alive is alive is alive
ICMP Host Unreachable from for ICMP Echo sent to
ICMP Host Unreachable from for ICMP Echo sent to
[ . . . ]

4rd: Check the arp table again:

borrajax@borrajax-pc:~$ arp -n | grep -v "incomplete"
Address                  HWtype  HWaddress           Flags Mask            Iface           ether   00:40:8c:e3:df:aa   C                     eth0           ether   e0:1c:41:30:ea:40   C                     eth0

Tadaaaa!! ether 00:40:8c:e3:df:aa is the camera

share|improve this question
This is kind of hard to understand. The standard way would be to assign either a fixed IP, and/or a DNS hostname to the camera. If your vendor doesn't support that, you should probably give up - either because they're too stupid, or they genuinely can't support it at the moment because of whatever this mesh stuff is doing. Standard OpenWrt allows configuring fixed IPs for a given MAC (and then you can also add a DNS hostname for the IP if you want). – sourcejedi Oct 5 '13 at 17:44
As OpenMesh puts it, I think you want a DHCP reservation.… – sourcejedi Oct 5 '13 at 17:50

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