R700 dropping Bonjour mDNS packets but 7982 is not

[john_d]

I've got a standalone R700 running the 9.8.0.0.373 GA, and have been having issues with unreliable Bonjour discovery on the 5GHz radio. The network is a pretty simple topology, all under the same subnet, with two wired Time Capsules and 3 Apple TV's on the wireless segment.

The problem is after a few hours, associated 5GHz clients can no longer see the Apple TV's in the Airplay list, and Time Machine backups also fail on desktops due to the Time Capsule's Bonjour service no longer being discoverable.

If I take a packet dump on the machine originating the query, I see a multicast DNS query go out, looking like:
jdrmbp.mdns > 224.0.0.251.mdns: [udp sum ok] 0 PTR (QU)? _ssh._tcp.local. (33)
08:39:22.641080 IP6 (flowlabel 0xaa868, hlim 255, next-header UDP (17) payload length: 41) jdrmbp.local.mdns > ff02::fb.mdns: [udp sum ok] 0 PTR (QU)? _ssh._tcp.local. (33)

But no response. And if I tcpdump on the wired segment of the network, I simply see nothing. It's as if the R700 itself is discarding the multicast query.

If I lock all clients to a 2.4GHz wlan, then wired and wireless Bonjour discovery works. I've gone through several suggestions from support (case 00189250), but none of them are helping, including:

- Setting directed-thr to 0 for all wlans
- Setting qos directed multicast disable for all wlans
- Playing with encryption settings (using WPA+WPA2 mixed instead of WPA2 AES)

As another data point, I set up a Zoneflex 7982 with the exact same configuration (the first two items on this list, I left encryption as WPA2-AES) and Bonjour works perfectly fine even after 48 hours, even on 5GHz.

Any suggestions would be greatly appreciated!

[john_d]

Not really -- as soon as support heard that adding a ZoneDirector fixed the issue, they told me that a ZD is required for Bonjour to work correctly (which certainly doesn't sound right). I lost the motivation to look more into it as well -- the time cost of trying to fix it combined with the continuous network disruption of trying new settings was starting to outweight the cost of adding a ZD anyway.

But at any rate, it sounds like 9.8.2's release notes mention fixing a broadcast issue on 802.11AC AP's. Perhaps that finally resolved it?

[michael_brado]

Hi John,
Let's explore this Bonjour behavior on R700 thru your SF#253939 ticket. Venkat
will provide our 100.x image for further evaluation, and if you still see issues, we
need to file a new bug. Thanks.

[john_d]

Hmm, can anyone else reproduce this issue chime in? Since my ticket, I've added a ZD to my network, and I don't *really* want to take my R700 out of service to reproduce this issue.

Hopefully if someone else has this problem currently, they can try this out in a new support contract.

(I wouldn't be mad if you guys have an extra R700 to spare for reproducing this issue :D)