Miracast Issue For Laptop

[VivekT]

Hello Everyone,

I’m working with a Meraki ecosystem, specifically using the MR57 model. We typically project our laptop screens onto a Samsung TV using the Windows + K shortcut. This works most of the time, but it’s not always stable.

Occasionally, the connection fails. I’ve already whitelisted the TV in Meraki Air Marshal, Microsoft TAC was unable to assist.

Has anyone encountered or resolved this issue before?

[PhilipDAth]

Is the TV Ethernet or Wireless connected?  Is the laptop Ethernet or wireless connected?

Is "Deny Local LAN" turned off?

https://documentation.meraki.com/MR/Firewall_and_Traffic_Shaping/'Deny_Local_LAN'_settings_in_Cisco_...

[VivekT]

Thank you for your response!

The TV can connect via both Wi-Fi and LAN. However, we are using Wi-Fi for Miracast services, so we can consider it connected over Wi-Fi.

During Miracast usage, both the laptop and TV are connected via Wi-Fi, though they might be on different SSIDs.

The "Deny Local LAN" option is enabled because I want to block the guest SSID from accessing our internal LAN.

The setup flow is: AP → Switch → MX.

When I project the laptop screen onto the TV, a virtual Wi-Fi Direct adapter is created with an IP range of 192.168.xx.

Out of 10 attempts, the same setup works about 7 times, but it operates in an ad hoc manner.

[PhilipDAth]

I don't think you'll be able to use "Deny Local LAN" in this case.  You'll need to create a firewall rule to block access to your internal LAN.  The SSIDs involved will need to be in bridged mode.

I assume the SSIDs are in different VLANs.  You will probably need to play with Bonjour forwarding options.

https://documentation.meraki.com/MR/Client_Addressing_and_Bridging/Bonjour_Forwarding

The device doing the routing between the VLANs might need to be Bonjour capable as well.

[VivekT]

I have this.Do you think this will give problems for wifi direct /Miracast ?

I see the option for bonjour forwarding but I do not see option for MerakiCast/Wifi Direct

[PhilipDAth]

That looks good.  I think that will increase your chances.

[AnthonyN]

Do you have multiple switches in your network? 

Does Miracast work if the clients are connected to an AP that's connected to the same switch the TV's AP is, but not if its a different switch?

In that case, you may need to enable an IGMP snooping querier on one of your switches. 

[VivekT]

Hello ,

Yes , we do have multiple switches. Two switcches we have dedicated for APs only. MR57 using two ports , one cable is going on 1st SW and 2nd one to another.

Still do i need IGMP snooping querier ?

[VivekT]

I tried to capture the logs.. during this time I was not able to project my screen on TV. Can you help to interpret the logs if possible ?

[AnthonyN]

You can see the device 192.168.137.1 is trying to Join a multicast group using IGMPv3

If the traffic goes from one switch to another, you need to have an IGMP snooping querier configured on one of your switches. 

Review this doco here for more info about multicast

https://documentation.meraki.com/MS/Other_Topics/Multicast_Overview%2C_Configurations_and_Best_Pract...

[PhilipDAth]

Check out this detailed post on multicast routing.

https://community.meraki.com/t5/Switching/Multicast-Basic-s/m-p/25867/highlight/true#M2125

[VivekT]

When I look into the Wireshark logs, there is direct communication between laptop and TV (peer to peer). The IP subnet is 192.168.137.xx which is non routable in my enviornment.

So do we think enabling IGMP config will help here ? I am just trying to understand here

[AnthonyN]

If the AP the laptop is connected to, is on the same switch the TV is connected to, then you wont need the snooping config. However, you mentioned you have multiple switches in your network so you will need to have the snooping config. 

What IP address is the laptop and TV in your screenshot? The only other traffic I see there is NBNS (NetBIOS Name Service) between .1 and .255 which is essentially like DNS. 

[VivekT]

Hello ,

We have dedicated sw for access points, two ports from access point go to two switch (stack) in power sharing mode.

We get this Ip address when wifi direct(Mircast) is connected via WLAN virtual adaptor irrespective of TV/laptop conncted to our commapny ssid.

Laptop IP : 192.168.137.1 

TV IP : 192.168.137.247 

Scenario 1 : TV and Laptop connected our company SSID or Mobile hotspot

When we try Miracast

Issue : We see ad hoc issue while connecting

Scenario 2: TV and Laptop not connected to our guest SSID or Mobile hotspot (bit Wifi is enable in TV)

When we try Miracast

Issue : We see ad hoc issue while connecting