InterVlan and multicast routing on 2960 XR

[patricktodd1]

I have a setup that will require routing between 3 Vlans and have multicast contained within one of those vlans across 4 switches.

For controlling the mcast vlan I will enable IGMP Querier on the vlan on one switch and IGMP snooping on all the rest, or do I have to enable querier on each that has the Multicast VLAN? I do not want to use PIM.

To clarify:

VLAN101

VLAN102

VLAN103 - Multicast on this vlan using IGMP Querier and Snooping

Route regular (not multicast traffic) between all 3. If possible am I able to route only VNC traffic from VLAN101 to 103, and all traffic from 102 to 103?

Would the 2960-XR be capable of this or would I need to upgrade to a 3650 for routing between the vlans?

[s.lachica]

Hi Patricktodd1,

2960 comes with either Lan-base or Lan-lite, so therefore, no routing between VLANs. You'll need 3650 for or other equipments with at least IPbase license to do this.

You do not need PIM if you are not doing IP Multicast (multicast over the network). Since your multicast is limited to a single vlan only, L2 multicast can handle these things without enabling anything.

Same with IGMP querier and snooping, they wouldn't work without PIM enabled on the interfaces.

Regards,
Son

[patricktodd1]

Thankyou for your help;

http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-2960-x-series-switches/qa_c67-728348.html

the XR can have IP Lite, is that sufficient to do intervlan routing or is IP Base necessary?

Same with IGMP querier and snooping, they wouldn't work without PIM enabled on the interfaces.

I thought the IGMP querier is a layer 2 construct and PIM is a layer 3?

I know that multicast can work in a single vlan, but it works as broadcast, IGMP snooping is suppose to prevent broadcast storms by only sending multicast to senders and receivers, the IGMP Querier function is to setup Mrouter ports to allow that to cross switch to switch. Right?

[s.lachica]

Hi Patricktodd1,

If you have IP Lite license(thanks Reza), then yes you can do inter-vlan routing locally on that switch.

For IGMP querier, not sure, but as far as I know, IGMP are requests sent by multicast receivers to Routers running PIM. So, no PIM, no reason for using IGMP features. This is just my thought.

Regards,

Son

[s.lachica]

Hi Patricktodd1,

Based on my understanding, if you have IGMP messages going on, then you need IP multicast enabled, and therefore PIM must be enabled on the SVI of that VLAN.

Regards,

Son

[Jon Marshall · Accepted solution]

Patrick

You are correct, the IGMP snooping querier is used to send IGMP queries when you have not enabled PIM on the SVI for that vlan.

You only need to enable it on one of your switches.

You can control which vlans VNC traffic is allowed between using acls on the SVIs.

Jon

[Reza Sharifi · Accepted solution]

The 2960 XR should not have any issue routing between vlans as long as you have IP Lite license.

see below:

Q.    What are the notable differences between the Cisco Catalyst 2960-X and 2960-XR switches?

A.     The Cisco Catalyst 2960-XR switch models have the following additional capabilities in addition to the features in the 2960-X models:

●   Dual-FRU power supply with integrated fan

●   Layer 3 features with IP Lite feature set

●   Configurable 8 queues per port (standalone)

●   48 Ether channel groups

Link:

http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-2960-x-series-switches/qa_c67-728348.html

HTH