[Xorp-users] XORP - Linux - Multicast setup help

[Bruce Simpson]

Hello,

Sorry for the delay in replying to your message.

Lucky Stud wrote:
> Hi,
>
> I am trying to setup the xorp on a linux (RHEL4) machine with 3 
> interfaces which routes the traffic for two subnets (setup below). 
> eth0 is directly connected to the a cisco router. I need to enable 
> multicast routing in order to be able to use norton ghost and 
> multicast to image the machines in the 192.0/26 and 192.64/26 subnets 
> and also to receive a multicast video feed transmission from internet. 
> cisco router is setup properly as I can use multicast on all other 
> subnets that are directly connected to the cisco router. The two 
> subnets behind the linux router are live ip and not natted.
>
> I am not sure how to setup the static-rps and/or the bootstrap for the 
> pimsm4 directive to get it to work properly. which interface needs to 
> be the BSR or RP or just use the static rps.

I'm assuming that you don't already have any other multicast routers 
deployed in your network, possibly apart from the Cisco device. Is it 
configured as an RP?

    For a 3 armed router with two stub networks, the placement of the RP 
is not really going to be an issue, however PIM-SM does need one in 
order to operate. I can foresee that you may have trouble with your 
video transmission requirement -- you don't specify if your upstream ISP 
runs PIM-SM already, or if you are able to peer PIM-SM with them. XORP 
does not currently support PIM-DM, and it is generally not widely deployed.

    If your ISP only speaks IGMP on customer networks, you will most 
likely have to install a third-party IGMP proxy, as XORP does not 
currently support IGMP proxy mode. If your ISP does however speak PIM-SM 
on customer networks, then you will have to contact them and ask them 
for the RP configuration details, assuming they do not support the PIM 
bootstrap mechanism.

There is also auto-rp, however, that is somewhat proprietary in nature, 
see Pavlin's old post on the subject:
    http://www.mail-archive.com/xorp-hackers@icir.org/msg00001.html
...if your Cisco device has the necessary IOS feature set, then you 
might just have to use that instead.

In your situation, I would configure your XORP router to be a static RP 
using the configuration you've posted, which looks as though it should 
work properly, although obviously I haven't tested it. Your zone scope 
should be OK for a stub/customer network, but I wouldn't use that 
configuration in a carrier network.

If you are having problems with this config, please post the error 
messages and/or describe the behaviour you see. Currently there is a 
known issue with the MFEA that each network port must have active 
Ethernet link pulse in order to work. There is a community patch for 
this which currently isn't in upstream source, please see the xorp-users 
archives.

thanks,
BMS