This Cisco reference document about mDNS and Chromecast devices should lead you to the solution on Aruba I hope.
https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-mobility/119017-config-chromecast-mdns-wlc-00.html ********** Replies to EDUCAUSE Community Group emails are sent to the entire community list. If you want to reply only to the person who sent the message, copy and paste their email address and forward the email reply. Additional participation and subscription information can be found at https://www.educause.edu/community
