[Xorp-users] OLSR test results on Linux.

[Ben Greear]

On 07/09/2009 12:48 PM, Bruce Simpson wrote:
> Ben Greear wrote:
>>>
>>> Multicasting isn't supported by XORP's OLSR implementation at the
>>> moment; that's likely to need kernel patches.
>>
>> Ahh, but if I run pimsim beside it, it seems to work.
>
> Please do NOT deploy this in a production network :-)
> There is no loop detection, and the non-tunneled multicast traffic may
> loop back, possibly causing meltdown.

Where is the loop detection lacking?  Is this any different from running
OSPF and pimsm beside it?

> Of course, if you are just using it to receive multicasts at most 1 hop
> from the OLSR router, you might get away with it -- providing none of
> the OLSR nodes are enabled as multicast forwarders.

Our use case is multiple OLSR (xorp) routers in a mobile mesh network.
Anything transmitting or receiving multicast will be directly attached
to a router in the normal case.

We did the same thing with OSPF & multicast routing and it seems to
basically work that way at least.  From looking at the routes that OLSR
generates (for a simple network, at least), it seems pretty similar to
what OSPF does.

> But I strongly recommend not doing this in production, until there's at
> least histogram based duplicate detection, which does need help from the
> kernel.

I'm not afraid to hack the kernel :)

Got any pointers to what you are talking about here?


Thanks,
Ben

-- 
Ben Greear <greearb at candelatech.com>
Candela Technologies Inc  http://www.candelatech.com