SRX

Hi,

I'm new to JunOS, but so far loving it compared to Cisco, but I'm having touble with multicasting. This isn't something I've done before and I'm finding information on it a little scarce.

I have three SRX210 routers setup (in lab) with each router connected to each other with a /30 layer 3 link running OSPF. On the first router I have 2 video encoders running in multicast broadcastng to 239.0.0.1 and 239.0.0.2. On the third router I have 4 video decoders, two for each encoder.

This works fine if I have just 1 encoder running, but as soon as I turn on the second one I get packet order issues. I've plugged my laptop into one of the ports the decoders sit on and found that the router is just flooding the network with my multicast traffice.

My question is, how do I get the router to only send the traffic to the ports that need it for the specific stream?

Thanks

Andrew.

can you post your config(s)?

are the decoders in the same VLAN on the SRX?  If so, I would try to enable igmp-snooping for the VLAN they are on.  That should cause it to only forward the multicast to the ports that it has seen IGMP Joins come in.

will

Sorry for the delay in replying.

I have now got this working, almost.

You were right about igmp-snooping and this has indeed stopped the packet flooding, however, I now see lots of packet errors when I have two encoders on the network but it's not a result of flooding.

I thoughts this may be a software / hardware issue so I have got an SRX240B unit to compare the setup to, but now I am unable to get the layer 3 routing of multicast packets to work.

My protocols and security section looks like this (on the SRX240)

protocols {
    igmp;
    ospf {
        area 0.0.0.0 {
            interface vlan.0;
            interface vlan.1;
            interface vlan.2;
            interface lo0.0;
        }
    }
    pim {
        rp {
            local {
                address 172.31.255.10;
            }
        }
        interface all {
            mode sparse;
        }
    }
    stp;
    igmp-snooping {
        vlan all;
    }
}
security {
    forwarding-options {
        family {
            inet6 {
                mode packet-based;
            }
            mpls {
                mode packet-based;
            }
            iso {
                mode packet-based;
            }
        }
    }
}

if I have the encoders and decoders in the same VLAN then it works, however as soon as I move the decoders into a different VLAN from the encoders I don't get any multicast traffic. Having looked at the show IGMP-snooping vlans output on the router they appear to be showing me the same thing, although I'mnot sure if IGMP-snooping really comes into effect in layer 2(?)

Does anyone have any suggestions? I have copied my protocols and security sections exactly from my SRX210 to my SRX240.

Just to clarify:

On the SRX210 the multicasting works across two vlans but there is heavy packet loss

On the SRX240 the multicasting works on a single vlan but not across two vlans

Thanks for any and all help

Andrew.

Eventually I got so frustrated with this not woring and opened up another SRX240 box to see if that worked. I copied and pasted the config from the dev unit to the new dev unit and it worked immediatly.

The issue seems to be the software version

Operating system version 11.2R4.3 does not work

Operating system version 10.4R3.4 works

I believe the recommeneded version is 10.4R9.2, does anyone know how I can get this to downgrade the 11 unit? I want to have all the boxes on the same version. When I go to the download link it says I don't have access, even though I'm logged in.

Thanks

Andrew.

Hi,

You can request for access to download the Junos Software 10.4R9( I think you need to have a support contract for this) .

and to confirm that the issue is with Junos Software image , we can do  a "request system snapshot" ( as we don't have download access) .

Currently , you have two SRX 240s one on 11.2(not working) and another on 10.4R3(working) .

1. On the working SRX240, insert a USB and issue "request system snapshot media usb" from the operational mode ( might ask you to partition the USB,just add partition option at the end of the previous command). 

2. Once the snapshot (backup the compact flash of working SRX240 to USB), disconnect it and connect it to non-working SRX240.

3. On this , issue "request system reboot media usb" from operational mode ,then it will reboot from USB, and after the login , issue "request system snapshot media internal" (to copy the contents of USB to internal compact flash of non-working SRX240) .

4. Once it is done , disconnect it and reboot, now both SRX240s will have the same Junos image i,e 10.4R3 and same configuration .

Now we can confirm whether it is the issue with Junos image or not .

Hi Pradeep

That has worked. Both routers are now able to route multi-casting traffic correctly.

Looking at the KB article it seems that 10.4 is the recommended release for the SRX240 anyway, not 11 so I will stick with the 10.4.

Thanks for your help. That's a great trick.

Andrew.