Switching

Hi everyone

Just looking for some guidance.  I am working on an EX3200 switch running Junos 10.056.  I am trying to get IGMP snooping to work properly.  I know by default that IGMP snooping is enabled be default on all Vlans, but the switch is blocking all my multicast traffic except for 224.x.x.x traffic.  I am trying to register and view 4 cameras, but i am unsuccessful in doing so. 

This is the set up:

1- EX 3200 switch - default settings.  All ports are in the default VLAN

4 - IP cameras that use multicast

1 - viewing stations

1 - Video headend system ( used to manage the camera registrations)

It seems that the switch does not allow multicast traffic to flow.  If i add the following line to the configuration:

set interfaces protocols igmp-snooping vlan all interfaces all multicast-router-interface, the 4 cameras register and pass video, but now the switch is flooding on every port with multicast traffic.

So my question is,  how does one configure IGMP Snooping on a single switch to manage multicast traffic without flooding using the default Vlans

I am used working on HP and Cisco switches.  the procedure is two steps, give the default Vlan an IP address then enable igmp snooping on the vlan and done.

I have read this article http://www.juniper.net/techpubs/en_US/junos9.5/topics/task/configuration/igmp-snooping-ex-series-cli.html    but it does not work.

Thanks

Luis

What multicast address are you trying to use that is not in the 224 address range?  Also, can you show the output of the following three commands:

show igmp-snooping vlans
show igmp-snooping statistics
show igmp-snooping route

Ron

Hi Ron

The the cameras generate a 239 or 238 address. 

Here is the output without being able to pass video

root@Switch1> show igmp-snooping vlans
VLAN                            Interfaces Groups MRouters Receivers RxVlans
default                                 24      0        0         0       0

root@Switch1> show igmp-snooping statistics
Bad length: 0 Bad checksum: 0 Invalid interface: 0
Not local: 0 Receive unknown: 0 Timed out: 0

    IGMP Type           Received      Transmited    Recv Errors
    Queries:                   0               0              0
    Reports:                  36               0              0
    Leaves:                    0               0              0
    Other:                     0               0              0

root@Switch1> show igmp-snooping route
VLAN             Group          Next-hop
default          224.0.0.0, *

Here is the output with flooding occuring when i apply the set interfaces protocols igmp-snooping vlan all interfaces all multicast-router-interface.

root@Switch1> show igmp-snooping vlans
VLAN                            Interfaces Groups MRouters Receivers RxVlans
default                                 24      0       24         0       0

root@Switch1> show igmp-snooping statistics
Bad length: 0 Bad checksum: 0 Invalid interface: 0
Not local: 0 Receive unknown: 0 Timed out: 0

    IGMP Type           Received      Transmited    Recv Errors
    Queries:                   0               0              0
    Reports:                  60               0              0
    Leaves:                    0               0              0
    Other:                     0               0              0

root@Switch1> show igmp-snooping route
VLAN             Group          Next-hop
default          224.0.0.0, *       1289

So from you question about the 224 address, does Junos only allow 224 by default?  It just seems like i am missing 1 or 2 config lines, but can't figure it out.  I have seen example where they statically set the mutlicat group address, but i don't want to have to do that.  I just want the switch to be able to manage all multicast traffic.

Thanks

Luis

I really have no experience with the 239 multicast range, so I do not know, I was just trying to understand what you are describing, and propose what might be happening.  Do you think there might be a way to add an entire range like 239.0.0.0/8?

Ron

hi,

first, I do not have EX to test/verify it and had no chance to play with multicast on the EX. Just guessing based on available info/docs. You have been warned !

From 'show igmp-snooping statistics' I see no IGMP queries, just reports. Is there a IGMP querier in the network ? EX Junos docs does not show the option to make the EX IGMP querier. No PIM router is the network, just single switch ?

You may configure PIM on the EX to make it a querier, or configure IGMP group membership on a port you want to receive the streams (viewing station ?).

I see 'charleschuckcharlie' post, but I'm not sure how 'since you are not routing multicast all you should need to configure is igmp-snooping using the "vlan all" statement' would help.

jtb

that's what I said.

Hey Libarra,

Since you are not routing multicast all you should need to configure is igmp-snooping using the "vlan all" statement, assuming that you would like to enable multicast for all.  Also, you should not have to do anything special for groups other than the locally scoped groups, 224.0.0.0/8, for joins to be processed by the switch.

That being said, I experienced real problems with multicast switching and routing in earlier versions of JUNOS (9.2 and 9.3).  For all issues, I opened up a ticket with JTAC as they were not configuration related.  The solution in each case was to upgrade to a different version of JUNOS.  I am currently running 9.3R4.4 in production.  The main reason I have not moved off of this release is because multicast works predictably, though I had an issue with once when I renamed several multicast enabled VLANs and RVIs.  I will detail what I did to fix this below.

To see what is happening in your case, I would do the following:

• in configuration mode, remove all protocol statements for igmp, igmp-snooping, and pim (delete protocols pim, delete protocols igmp, delete protocols igmp-snooping) and commit the configuration
• in configuration mode add back igmp-snooping (set protocols igmp-snooping vlan all) and commit the configuration
• find the multicast testing applications wsend and wlisten - these applications are indispensable as you can configure groups, ports, payloads, and TTLs - if you cannot find them let me know and I will try to post or email a copy - it runs on windows
• connect a host to the switch and prepare to launch wlisten, on the switch, monitor the interface in question using "monitor traffic interface interface no-resolve" 
• define a group and join - the "monitor traffic interface" command will display any traffic processed by the switch (by the control plane), so your igmp join messages should appear; here is the output from one of my joins and leaves:

...

18:56:16.671522  In IP 10.61.8.50 > 224.0.0.2: igmp leave 239.1.1.9

• using "show igmp-snooping membership"  you should see your port joined

Hi Carlos

thanks for the info...a coworker and i have been beating our heads into the wall....but we were able to get it working, but i am not sure if its the correct method....I will review you post again and compare it to our set up.....here is what we did

1. set the switch back to factory default

2. created and RVI for the default vlan

3.enabled IGMP

Even though IGMP-snooping is enabled, we discovered that it only filters the traffice and does not pass it.  When we enabled IGMP it passed the multicast traffice only to the requester and we are not flooding...see my partial config below

      }
    }
    vlan {
        unit 1 {
            family inet {
                address 192.168.5.1/24;
            }
        }
    }
}
protocols {
    igmp {
        interface all;
    }
    igmp-snooping {
        vlan all;
    }
    rstp;
    lldp {
        interface all;
    }
    lldp-med {
        interface all;
    }
}
ethernet-switching-options {
    storm-control {
        interface all;
    }
}
vlans {
    default {
        vlan-id 1;
        l3-interface vlan.1;
    }
}
poe {
    interface all;
}

All multicast sourced are now creating groups.....when i hooked up a second switch (switch2) with defualt settings, it found switch one and i am assuming made it its querier.  it is created groups, passing multicast traffice and not flooding. 

for now its working for us....like i said above..i will be reviewing your post again we just want to make sure we are setting this up correctly.  The Juniper whitepapers are confusing and they don't seem to give very good guidance for multicast layer 2 networks

thanks for the info,

Luis

Luis,

you mean, you had to enable 'protocols igmp interface all' to make it working ? I guess it enabled the IGMP querier on the EX. And yes, IGMP snooping is about filtering multicast traffic and will not work as expected without IGMP querier in the vlan.

'show igmp-snooping statistics' will show there are IGMP queries now. You can sniff the traffic to see periodic queries. And yes, the EX docs are not clear here.

jtb

Hi jtb,

yep 'protocols igmp interface all' is what i meant, thats why i posted my config also.  Yeah i was going nuts because when working with HP or Cisco, enableing IGMP snooping also gives you the querier(well once you asign and IP address to the default VLAN).  but yes i get all my IGMP stats and my other switches are seeing the querier with default settings, i don't even need and RVI on my other switches or IGMP enalbed on all interfaces....IGMP snooping is enough. 

Luis

There is a history with some JUNOS version not using default values in factory settings.

Could be why it it not working as assumed.

Move to v.10 of JUNOS 🙂