How Can I Pass Chromecast Or Bonjour Traffic Between Vlans?

By esupport posted Apr 06, 2020 05:59 PM


How can I pass Chromecast or Bonjour traffic between VLANs on the HPE/Aruba-OS Switch?


Chromecast and Bonjour traffic stays within a single subnet and is not forwarded into other subnets.
Normally, devices need to be in the same subnet to see Chromecast or Bonjour traffic from another device.

HPE's mDNS Gateway can be configured to allow the switch to forward Chromecast and Bonjour traffic into another subnet/VLAN.
Details about mDNS functionality and configuration options are listed in the "Multicast and Routing Guide" for the ArubaOS-Switch.
Here is a link to the 5400R/3810 Multicast and Routing Guide; mDNS information starts on page 449:

By default, when mDNS is enabled, all mDNS traffic is denied.
Create a Profile for each VLAN to specify which mDNS services are permitted on that VLAN.
For each profile, configure rules for which services are permitted or denied and which VLANs will use that profile.
The default behavior is to deny, so you can use the 'permit' option to specify which services to allow.
Configure the mDNS Gateway to specify which VLANs can forward mDNS traffic.

Note: In order for mDNS Gateway to forward Chromecast or Bonjour traffic between VLANs, those VLANs must have an IP address configured.

Example Config:
To pass Chromecast traffic between VLAN-2 and VLAN-3:

mdns enable
mdns gateway vlan 2,3
mdns profile Chromecast
 rule 1 service googlecast action permit
 rule 2 service googlezone action permit
 vlan 2,3

vlan 2
 name "VLAN-2"
 untagged 1-12
 ip address
vlan 3
 name "VLAN-3"
 untagged 13-24
 ip address
Since both VLANs will only be passing Chromecast service traffic, they were both configured under one profile.
Different profiles can be created for each VLAN with different allowed and/or denied services.
The googlecast service is used with Apple devices.
The googlezone service is used with Google Chrome web browsers, including Windows systems.
If Chromecast needs to pass between an Apple device and a Windows device, be sure to permit both services.
There are many mDNS services for Bonjour traffic.  Here is a partial list of some common Bonjour services:
Application         Service               Description
-----------               -------                    -----------
AirPlay:               raop                    (Remote Audio Output Protocol)
AppleTV:            airplay                 (Apple TV)
AppleTV:            appletv-v2          (Apple TV Home Sharing)
AppleTV:            touch-able         (Apple TV Remote APP (IOS Devices))
iTunes:               atc                       (Apple Shared iTunes Library)
iTunes:               home-sharing   (iTunes Home Sharing)
DigitalAudio:     daap                   (Digital Audio Access Protocol)
AirDroid:            airdroid              (AirDroid App)
AirPrint:             ipp                       (Air Print)
Printer:              universal            (Universal/Shared)
Printer:              print                    (Universal/Shared)
Printer:              cups                    (Universal/Shared)
Chromecast:     googlecast         (Apple Devices)
Chromecast:     googlezone       (Chrome Web Browser)

To check the configuration and operating status of mDNS, use the following commands:

show mdns                    (Shows if mDNS is enabled or disabled.)
show mdns gateway    (Shows which VLANs mDNS traffic can forward between.)
show mdns profile       (Shows each configured profile, which VLAN(s) are configured for that profile, and the rules for each profile.)
Here is a link to a helpful video showing how MDNS Gateway works and how to configure profiles for different Bonjour services on a HPE Aruba-OS Switch: