Network Loop and broadcast storms with Sonos


I was at a Sonos Training event today and was told if I connected multiple Sonos Connect Amps located in a closet or rack to an unmanaged switch via Ethernet cable I was fine as long as I didn't daisy chain the cat5 cable from Connect Amp to Connect Amp but connected a single cable 5 cable from each connect amp to the switch. The sonos trainer said daisy chaining would cause a loop and broadcast storms. Then an hour later I sat through another vendor training that warned if you connected two connect amps to a switch with single cat5 each they would cause a network loop because they would still communicate through the wireless mesh cause network loop creating broadcast storms. I also forgot to ask what if I had 4 Sonos Connect amps connected via single cat5 each to unmanaged switch, 1 boost connect to switch, 2 playbars connected via cat5, 2 paired Play1 connected wirelessly, and 1 Sub paired with Playbar connected to network by Cat5 cable to switch. Have I created a problem?

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BTW the article you linked says "Also, a managed switch with Spanning Tree Protocol (STP) running should do the trick." This has always been an officially supported solution. Most dumb switches don't cause problems either.
Supported, yes, as long as Spanning Tree is configured correctly. i.e. reduce the priority to make your switch the root of your network (it wouldn't be good if one of those Sonos devices two layers in thought it was the root because it had a lower MAC address than the rest of the Sonos devices and the switch), ensure the path cost values are set correctly (Classic STP is often available on many smart/managed switches, but may not be the default).
The trainers provided incomplete and/or inaccurate information. Read here.
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Daisy chaining or direct wiring each CONNECT(:AMP) to a switch in theory doesn't matter. (However, if the switch is modern, using the current STP version, then Sonos' ancient STP implementation with small cost values will cause sub-optimal path selections and may be the genesis of what these trainers were advising.)

However, you may want to consider disabling the WiFi on some or all of the units in the rack, as having a bunch of them blasting away on the same radio channel in such close proximity will just create a lot of interference. Google "disable sonos wifi" for more details. If you have at least one remote wireless Sonos device then leave WiFi enabled on just ONE of the CONNEECT(:AMP)s in the rack (and if daisy chaining, I'd do this on the one directly connected to the uplink (e.g., switch)). If you have no wireless Sonos devices, or they have better radio connectivity (less interference) to a wired Sonos located elsewhere than the rack, then I would disable WiFi on all of the units in the Rack. This will eliminate radio interference, and save about 2W of power per Sonos device that disables WiFi.
if the switch is modern, using the current STP version, then Sonos' ancient STP implementation with small cost values will cause sub-optimal path selections and may be the genesis of what these trainers were advising.
That wasn't my reading. Trainer comments such as "daisy chaining would cause a loop and broadcast storms" and "if you connected two connect amps to a [single] switch with single cat5 each they would cause a network loop " suggested they had the wrong end of the stick. Nothing to do with path costs.

you may want to consider disabling the WiFi on some or all of the units in the rack, as having a bunch of them blasting away on the same radio channel in such close proximity will just create a lot of interference.

No interference. They'll simply compete for bandwidth, and most of them won't have much to transmit.

save about 2W of power per Sonos device that disables WiFi.

Yep, that's true.
Userlevel 7
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Daisy chaining would not create a loop. The only way Sonos could cause a loop through a switch is if multiple switch ports are used.

Individual connections to a switch CAN create a loop, depending on how the switch handles STP BPDU packets.

ratty's link above should have all kinds of info on Spanning Tree and how Sonos uses it. If you have any other questions, ask and we'll answer!

STP = Spanning Tree Protocol
BPDU = Bridging Packet Data Unit
I am also worried the sub being wired and communicating with the mesh might be an issue too. I will take the suggestion to disable the wireless on those Connect AMPS that are in the racks and connected directly to the switch.
The SUB can stay wired. If you have a functioning system you can stop worrying about it. A broadcast storm caused by an undetected loop will take the network down immediately. (There are cases where a marginal wireless connection closes a loop intermittently, but they're pretty rare.)
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I have 3 Sonos Connects in a rack, and then we have the outputs digitally connected via co-ax to a "NetStreams DigiLInX" MLA4000. Which really has nothing to do with my question. I have disabled the Sonos WiFi. But we have heard that this now places all the "streaming" onto the regular network. Anyway to keep the "Sonos Streams" off the regular network? I have a managed switch, Unifi 48 port, wondering if I can apply a MAC filter to kill this, or would I need to do this just on one port and then loop the network connection from Sonos to Sonos.
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If you want to keep the audio streaming off of the "regular" network, then you need to create a separate network, which will have separate IP Addresses and everything. However, if the router at this business or home doesn't support multiple networks, what you're asking for may not be possible without a significant upgrade to the network.

Since you have a managed switch, you could create a new VLAN and set the ports that your Sonos players are connected to so they are access ports on that VLAN (or set one port that way then daisy-chain the three players together). However, the router would need to support VLANs (and I don't know of any consumer or SOHO router that does), so that you could set up a separate IP address range for this "Sonos" network.

By the way, Sonos uses very little bandwidth. If all three Connect players were streaming lossless FLAC audio - different songs from different sources to use the largest amount of data - then those three Sonos players would likely be using less bandwidth than a single Netflix movie streaming in HD. So if there is concern that Sonos will overload the network, it's not really likely.
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we could setup VLAN on our network. Might give that a try (VLAN), more worried about other things effecting my control system, and general wifi. But knowing your other statement now, might look into other things on the network causing issues.

Thanks
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I have what I consider a VERY large Sonos site; which I designed and recommended to my customer.
It has 18 Sonos zones in a single rack using a combination of Sonos Connects and Connect Amps. All these players are HARDWIRED - every three Sonos daisy chained to one switch port.. The network infrastructure is a pure LUXUL site. 5 APs, EPIC 4 Router and managed switch. STP is enabled. also have Domotz monitoring. I have been seeing network loops almost daily now. maybe every other day. for no apparent reason. Customer is so pissed that he is threatening a lawsuit because when the network loop occurs it renders the entire network unuseable. When the network loop occurs, you cannot even access it remotely. Simply a disaster for this customer. I and Luxul have been chasing these loops for over a week.
no luck isolating what is causing this;after STP is enabled, per Sonos guidance no less, right? I was under the impression
enablng STP would stop these.. not exactly.

Then I saw this article: https://www.cepro.com/article/turn_off_sonos_wifi_wireless_domotz
( Domotz apparently reverse engineered this functionality and put it into their interface. that's how important it was.)

I was able to go into each Sonos play remotely and disable its WIFI interface since they are all hardwired. NETWORK LOOPS stopped they have been running for almost 4 days now without a single episode.

I sent email to Sonos asking if they had heard of this Domotz capability and if they knew or could verify these conditions:
- does this setting persist across a reboot, power cycle, and thru a Sonos update.
The support guy I got was totally unaware of this. I asked him if he could do a test for these conditions. he refused
said it was a totally unsupported function.

Sonos please pull your head out of the sand on this one and help us custom integrators. This ALMOST cost me a lawsuit.

I need to know if I have to redo these changes EVERY TIME you send out a SONOS update to the players.
I need to know if I have to redo these changes EVERY TIME you send out a SONOS update to the players.
Not with the direct interface via a browser to port 1400, so long as you use the 'Persist Off' option. The setting then persists across reboots and firmware updates. It doesn't survive a factory reset, obviously.

You'd need to ask Domotz which option they use in their HTTP POST.

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BTW the article you linked says "Also, a managed switch with Spanning Tree Protocol (STP) running should do the trick." This has always been an officially supported solution. Most dumb switches don't cause problems either.
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STP has always been enabled on the switch BTW. I checked with Domotz, their feature already selects 'Persist Off'. Their interface allowed me to do this all remotely. Saved me a trip to the site and having to hack each Sonos thru HTTP. very nice feature imo.

But really, Sonos.... shouldn't you have an advance settings tab with a radio-button for this? With network loops being such a difficult issue to isolate and resolve. In my situation - these network loops went on for 5 months; they were intermittent. sometimes the site would go for ways without a single one. Then all of a sudden BOOM! there they are, then the entire network crumbles. Reboot the system and it goes away again.
Here I am thinking: "It can't be Sonos... STP is enabled, all the players are hardwired.. must be some other device."
I'd go there are turn on the players and they would work. I've sent you countless diagnostic reports, which showed no issues.
This issue really ate my breakfast, lunch, and dinner..:(
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BTW wrt VLANS - Sonos Controller (aka, mobile devices - all of them - HAS connect to the same VLAN as the players; if you create a VLAN for the SONOS. This scheme doesn't work at all for a Luxul environment with WAP controller that uses a single SSID. and the Sonos Controller is on, say a multi-purpose iPAD or even your mobile phone. Having two switch to another SSID to use Sonos, is at best an inconvenient use case.