[OLSR-users] OLSR Linux Network newbie questions

[Kim Hawtin]

Benjamin Watson wrote:
> Hello List,
> 
> I'm a first time poster and, quite frankly, new to OLSR and Linux
> networking, please forgive my long-winded post!!
> 
> I'm working on a wireless mesh networking project and have run into
> some road blocks.
> I'm sure I'm "almost there" and overlooking something trivial, so I
> thought I'd get some insight from the list.
> 
> What I'm attempting to do is set up the following scenario:
> 
> Laptop 1 <--link A--> MeshRouterA <--OLSR link B--> MeshRouterB
> <--Link C--> Laptop 2
> 
> The Mesh routers are Metrix Mark II kits with 2 wireless radios and an
> ethernet port running Pyramid Linux with olsrd available.
> 
> Link A is an 802.11b link where Laptop 1 is in client mode and one of
> MeshRouterA's radios is an access point serving DHCP.
> Link B is an 802.11a link where one radio on each MeshRouter has the
> same channel, essid, and is set to ad-hoc mode.
> Link C is similar to link A, only between MeshRouterB and Laptop 2.
> 
> I've decided to use the 10.0.0.0/8 ip range for expandibility and
> flexibility down the road for more nodes.
> 
> I've assigned the LinkA radio on MeshRouterA (wlan0) the following:
> IP: 10.128.1.2
> Mask: 255.255.255.0
> Broadcast: 10.128.1.255
> 
> Laptop1 connects to MeshRouterA and is assigned:
> IP: 10.128.1.79
> Mask: 255.255.255.0
> Gateway: 10.128.1.2
> 
> Similarly, for the LinkC radio on MeshRouterB (wlan0) the following:
> IP: 10.128.2.2
> Mask: 255.255.255.0
> Broadcast: 10.128.2.255
> 
> Laptop2 conneect to MeshRouterB and is assigned:
> IP: 10.128.2.175
> Mask: 255.255.255.0
> Gateway: 10.128.2.2
> 
> This is all wonderful, the laptops can connect to the APs, can SSH
> into them, etc.
> 
> For Link B, the MeshRouterA radio (ath0) gets:
> IP: 10.128.1.1
> Mask: 255.255.0.0
> Broadcast: 10.128.255.255
> 
> And the MeshRouterB radio (ath0) gets:
> IP: 10.128.2.1
> Mask: 255.255.0.0
> Broadcast: 10.128.255.255
> 
> The MeshRouters are successfully exchanging OLSR messages and I can
> see the nodes "linked" in a visualization graph.
> 
> Furthermore, MeshRouterA can ping Laptop 1, and all of the interfaces
> on MeshRouterB, but cannot reach Laptop 2.
> Likewise, MeshRouterA can ping Laptop 2, and all of the interfaces on
> MeshRouterA., but cannot reach Laptop 1.
> 
> The Laptops can obviously ping the MeshRouters they're connected to,
> but not the "other" MeshRouter or the "other" laptop.
> 
> I enabled OLSR on all interfaces for both MeshRouters and let
> MeshRouterA do an HNA announcement of 0.0.0.0 0.0.0.0 as it is
> connected to "the Internet" on eth0.
> 
> The routing table on MeshRouterA looks like:
> Destination  Gateway     Mask                   Iface
> 10.128.2.1       *            255.255.255.255   ath0
> 10.128.2.2   10.128.2.1  255.255.255.255   ath0
> 10.128.1.0       *            255.255.255.0       wlan0
> 192.168.0.0     *            255.255.255.0       eth0
> 10.128.0.0       *            255.255.0.0          ath0
> default        192.168.0.1 0.0.0.0                 eth0
> 
> The routing table on MeshRouterB is "similar".
> 
> I know OLSR doesn't actually route packets, but aids in setting up the
> routing tables and so long as port forwarding is enabled (and it is),
> packets should be routed according to the table.
> 
> However, I'm not getting the Laptop-to-Laptop communication I desire.
> 
> Any suggestions?
> 
> Thanks for tolerating my long post!!

i have just done something very similar. you could explore adding HNA
routes for the networks that are connected to the routers...

cheers,

Kim
-- 
Operating Systems, Services and Operations
Information Technology Services, The University of Adelaide
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