Inter-VLAN Multicast IP Routing using a 3560X switch

[Jeff Harned]

Hello All,

Using one WS-C3560x-24 Switch; SW Version 12.2(55)SE1.

I would like to expand my knowledge using VLANS centered around using just one switch.

My LAN configuration would consist of two source conversion units; one sending out multicast data with an address of  239.1.1.3

and the other with an address of 239.1.1.4.  I have two more conversion units as the destination units capable of receiving both

multicast data streams.

What I would like to do is use a VLAN configuration for the ports used on the switch and be able to route both multicast data

streams between the two destination units.  In other words, to be able to pass data between the two VLANs assigned to the

destination ports on the switch.

I have had excellent results using MVR (Multicast VLAN Registration) using a Layer 2 switch.  Now that I have a L3 switch

I would like to be able to use standard VLANs in a configuration.

I could use some help to get started!

Thanks.

Regards,

Jeff

[Reza Sharifi]

Hi,

If you want to have the devices in 2 different vlans, then you need to create to vlans with 2 SVIs and enable "ip pim sparse-dense-mode" on both SVIs.

Example:

vlan 10

exit

inter vlan 10

ip address xx.xx.xx.xx

ip pim sparse-dense-mode

no sh

vlan 20

exit

inter vlan 20

ip address xx.xx.xx.xx

ip pim sparse-dense-mode

no sh

Also add the proper physical ports to each vlan.

HTH

[Jeff Harned]

Hi Reza,

Thanks for your reply. 

You hit on an area that I have read, researching on how to setup this configuration.  As stated I have the two multicast addresses of  239.1.1.3 and 239.1.1.4.  The one part I do not understand is what is the ip address xx.xx.xx.xx in relation to the two multicast addresss.  Is this ip address another address that has to be created?

Thanks.

Regards,

Jeff

[Reza Sharifi]

Hi John,

Is this ip address another address that has to be created?

Yes, that is separate IP address you need for each SVIs.  You need to find out what IP scheme and what type (public or private) your organization use and get 2 subnets for your 2 vlans.

It would be something like this:

vlan 10

exit

inter vlan 10

ip address 10.10.10.1 255.255.255.0

ip pim sparse-dense-mode

no sh

vlan 20

exit

inter vlan 20

ip address 10.10.20.1 255.255.255.0

ip pim sparse-dense-mode

no sh

HTH

[Jeff Harned]

Hi Reza,

Need some help!!

I have been tying to configure the switch.  I understand that a SVI has to be assigned to a physical port.

Does this mean I require an IP Address to a VLAN and an IP Address for the physical port assigned to it?

If so, would you please explain?

Thanks.

Regards,

Jeff

[Jeff Harned]

Hi Reza,

Following your example and looking up info under cisco, ip pim sparse-dense-mode will not

enable. I assigned a VLAN with an ip address to a port but ip pim sparse-dense-mode will

not enable.  I could use some help here.

Thanks.

Regards,

Jeff

[fb_webuser]

Hi Jeff, I am assuming that you have created both layer 3 interfaces on the the 3560X switch and you are using IP Services license as well. I'm not sure if you have a special requirement but passing multicast traffic between VLANs would require you to enable "ip multicast-routing distributed" on the switch. Then configure the VLAN interfaces to use PIM-Dense mode as this would be the easiest. That way you can move your multicast traffic from one VLAN to another.

---

Posted by WebUser John Patrick Lopez from Cisco Support Community App

[Jeff Harned]

Hi John,

I have not done any configuration with this switch as of yet.  I am still tyring to figure out on how to do it!
Not having much experience, I do not know what you mean by "IP Services license" and what I'm and

" mean!

Would you explain?

Thanks.

Regards,

Jeff

[gwes]

You can configure an IGMP snooping querier to support IGMP snooping in subnets without multicast interfaces because the multicast traffic does not need to be routed.

Configuring the IGMP Snooping Querier

Follow these guidelines when configuring the IGMP snooping querier:

•Configure the VLAN in global configuration mode.

•Configure an IP address on the VLAN interface. When enabled, the IGMP snooping querier uses the IP address as the query source address.

•If there is no IP address configured on the VLAN interface, the IGMP snooping querier tries to use the configured global IP address for the IGMP querier. If there is no global IP address specified, the IGMP querier tries to use the VLAN switch virtual interface (SVI) IP address (if one exists). If there is no SVI IP address, the switch uses the first available IP address configured on the switch. The first IP address available appears in the output of the show ip interface privileged EXEC command. The IGMP snooping querier does not generate an IGMP general query if it cannot find an available IP address on the switch.

•The IGMP snooping querier supports IGMP Versions 1 and 2.

•When administratively enabled, the IGMP snooping querier moves to the nonquerier state if it detects the presence of a multicast router in the network.

•When it is administratively enabled, the IGMP snooping querier moves to the operationally disabled state under these conditions:

–IGMP snooping is disabled in the VLAN.

–PIM is enabled on the SVI of the corresponding VLAN.

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_55_se/configuration/guide/swigmp.html#wp1193337