Virtual Router to Support Multicast

##### ISSUE TYPE

* Improvement Request

##### COMPONENT NAME

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Virtual Router
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##### CLOUDSTACK VERSION

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4.19.1.1
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##### CONFIGURATION

##### OS / ENVIRONMENT

##### SUMMARY

Currently Cloudstack Virtual Router doesnt support Multicast from external networks (eg. Private Gateway).

In our case, our customers require multicast support because they decode Stock Market Feeds from the Stock Exchange. And Majority Stock Exchange distributes market feeds in ITCH format, which is Multicast.

In order to overcome this limitation now, we had to resort to VNF + L2 Networks.

I also have a curious question, if Cloudstack VR does not support multicast, then why is there a UDP Protocol option in the Network ACL Rules?

##### STEPS TO REPRODUCE

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##### EXPECTED RESULTS

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For VR to support multicast natively
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##### ACTUAL RESULTS

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VR does not support multicast at the moment.
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El issue identifica el Virtual Router de CloudStack y solicita compatibilidad nativa con multicast para redes externas, pero no menciona archivos, pruebas, comandos ni puntos de entrada. Empieza localizando la implementación de red del Virtual Router y las pruebas existentes de protocolos o enrutamiento. Se considera completado cuando el tráfico multicast funciona de forma nativa a través del Virtual Router para el caso de uso descrito de redes externas.

Escrito por el modelo de indexación a partir del texto del issue.