Unicast to multicast reflection on a cisco 9300 switch

[Andreas Gutt]

Hi,

I need to convert a unicast stream to a multicast stream on a cisco 9300 switch with IOS 17.12. I only found solutions by creating an interface Vif1, but I cannot create such an interface on this switch.

Is there another way to convert unicast to multicast with a cisco 9300 switch?

Thanks for your help

Andi

[Jens Albrecht · Accepted solution]

Hello @Andreas Gutt,

the Cisco Catalyst switches do not support the "Vif" (Virtual Interface) service reflection feature that you are talking about. This feature is typically found on routers but not available on the switching platform.

The easiest solution is to change the source to natively generate multicast if possible.

If this is not possible, the common workaround is to use an external conversion host like a small Linux host or VM. There are a couple of tools like socat, VLC or tsplay for this purpose.

HTH!

[M02@rt37]

Hello @Andreas Gutt 

What is that unicast stream, where it come from ? What is the source protocol ?

[MHM Cisco World]

yes we need more detail 
MHM

[Andreas Gutt]

We need to provide a video stream, which we can send via unicast or multicast.

The customer has multiple sites, which are connected via a slow network. In each site LAN there is one cisco switch. On the network between the sites multicast is disabled. In the sites there are many clients who need the video stream. Therefore we want to send the stream to each switch as unicast and deploy it in the site LAN as multicast.

[M02@rt37]

ok @Andreas Gutt 

Thanks for that clarification. If you need on LAN to deliver that video by multicast you have to configure IGMP on c9300.

If you want to route multicast between sites, since "the network between the sites multicast is disabled", you should need to encapsulate multicast into GRE tunnel and activate multicast on each GRE ends.

--

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/software/release/17-12/configuration_guide/ip_mcast_rtng/b_1712_ip_mcast_rtng_9300_cg/configuring_igmp.html

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/software/release/17-12/configuration_guide/rtng/b_1712_rtng_9300_cg/configuring_generic_routing_encapsulation_gre__tunnel_ip_source_and_destination_vrf_membership.html

[MHM Cisco World]

https://ine.com/blog/2008-05-06-understanding-the-ip-multicast-helper-map-command

Check this 

MHM

[Andreas Gutt]

Hi,

thank you for your tipps.

Our customer sent us only one switch for the evalution in our reference system. I will try to get a second switch to test your recommendations.

I´ll keep you informed as soon as I can continue

Regards

Andi