Re: [qpimd-users] Issues with mroute in PIM

[Everton Marques]

James,

qpimd configuration should be easy, but it is hard to predict the exact difficulty you could be hitting.

Start by having a look at these guides:

a) http://git.savannah.gnu.org/cgit/quagga.git/tree/pimd/TROUBLESHOOTING

b) http://git.savannah.gnu.org/cgit/quagga.git/tree/pimd/DEBUG

Aditionally, qpimd requires understanding of PIM ASM versus PIM SSM.

It may be useful to check this:

c) http://git.savannah.gnu.org/cgit/quagga.git/tree/pimd/WHY_SSM

Once I sketched this brief overview of ASM vs SSM:

1) A host usually uses IGMP to join an any-source group like
239.1.1.1. The PIM router injects such a membership information into
the PIM protocol. The ASM (any-source multicast) service model is
implemented by full PIM-SM routers in order to dynamically build the
multicast distribution tree for that kind of any-source group.

2) qpimd does not support the ASM model. It only supports the SSM
(source-specific multicast) model. The difference is, SSM relies on
reception of source-specific joins. A source-especific join requires
IGMPv3 in order to specify the source for the multicast traffic.
Hence, while with ASM a host joins a group like 239.1.1.1, with SSM a
host must join a pair source+group. The pair source+group like
(2.2.2.2,239.2.2.2) is called an SSM "channel".

3) In order to run qpimd for dynamic multicast, you will need to tell
your member hosts
to join a channel like (2.2.2.2,239.2.2.2) and NOT simply join a group
like 239.1.1.1. This usually means that (1) the member host's
underlying operating system must support IGMPv3 and (2) the member
host's application must specify the multicast source address in the
join request.

4) It is worth mentioning SSM relies on the correct unicast routing of
the multicast source address towards the host which sources the
multicast traffic. That is, make sure the unicast routing towards the
source address is correct, either dinamically or statically.

5) If you have multiple PIM routers, you will want to enable "ip pim
ssm" on the links linking them.

6) Enable both "ip pim ssm" and "ip igmp" on qpimd router's interfaces
attached to member hosts. "ip igmp" enables reception of IGMPv3 joins.
"ip pim ssm" injects the IGMP local membership information into PIM
protocol.

-x-

If you spot any specific difficuly, please let me know.

Everton

On Tue, Apr 26, 2016 at 11:20 AM, jbarnes mti-systems.com <address@hidden> wrote:

Hi all,

I am relatively new to PIM and have been running into some issues. When running qpimd, I have only been using two interface configuration commands(pim ssm and igmp), which allows my hosts to form their  adjacencies, but nothing comes up in my mroute table. Are there more configuration commands needed to properly run qpimd(I am trying to run pim on quagga 0.99.24.1)?

cheers,

James Barnes