Contents
Overview
Chromecast (as well as AirPlay) utilize a discovery protocol to advertise services on a device. This is done through Multicast DNS. mDNS is a link local discovery protocol and therefore doesn't traverse VLANs natively.
Configuring a HP Procurve
Enable mDNS
conf t mdns enable
Configure the nDNS Gateway
conf t mdns gateway vlan 100-103,110
Create a mDNS Profile
conf t mdns profile "Google" rule 1 service "googlecast" action permit mdns profile "Google" vlan 100-103,110
Enable IGMP Snooping
IGMP Snooping allows the switch limit multicast to only ports that are using it.
conf t vlan 100-103,110 ip igmp
Verify IGMP
You can check which ports have IGMP traffic by running the following command:
sh ip igmp
or for a specific VLAN
sh ip igmp vlan 110
Testing
1. Place a Google casting device on one of the VLANS listed above (lets say 110), and your mobile phone on another (say VLAN 103). Now try to cast from the YouTube or another Cast capable app. You should see your Google cast devices.
2. No devices listed? Check Verify IGMP. If you don't see any ports listed then mDNS traffic isn't present on your switch.
3. No IGMP Traffic? Check your Access Point configuration and ensure mDNS traffic is permitted. Some AP's and WiFi Routers block or shape mDNS traffic.
4. Still no action? Set the global mDNS action to permit traffic in and out for testing.
conf t mdns default filter in action permit mdns default filter out action permit
5. If you see cast devices now, then you may need to change your "Google" mDNS profile from the Create a mDNS Profile section. Its likely the service name is wrong. Service name discovery is beyond the scope of this article. Try googling for 'Chromecast mDNS Service Names'