Interoperability issue with HDHomerun4K and Ubiquiti switches

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jmtripp1
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Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by jmtripp1 »

Hi All-
I just got done troubleshooting a super-annoying issue that I finally resolved that I thought I'd share in case it saves someone else some pain. I've had a working HDHomerun Connect 4K for some time now and it was working great until one day.....

Symptom: Red blinking network LED on the back of the Homerun box and no connectivity to the device. Power cycling the box didn't help, changing network cables and moving the device to a new port on my switch did not help.

After some basic troubleshooting, and SiliconDust actually sending me a replacement unit (thanks!), what it came down to is that some combination of the latest HomeRun 4K firmware and the latest Ubiquiti switch firmware (tested on both a Flex Mini and a US-8-60W) is causing the network link speed auto-negotiation to fail. Forcing the switch to 100Mbps FDX resolves the issue and allows the device to connect normally. An older HDHomerun Connect Quatro connected to the same switch port does not have the issue when set to auto-negotiate on the switch.

Just an FYI in case anyone else sees the issue and a big thanks to tech support for getting me a replacement unit when we thought the box was bad.

signcarver
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by signcarver »

Years ago nearly any consumer/prosumer netgear gigabit switch I tried did something similar (edit: with a prime). What was happening for me was the first 3 stages of dhcp would occur but just before the last, the switch would decide to negotiate again (and there were other devices that had the same problem with those 1st and second gen netgear gbps switches)... I have never seen such issue when the device itself (as opposed to the switch) was 100Mbit.

Also one typically needs to turn off STP on such ports going to the hdhomerun.

csdesigns
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by csdesigns »

Be thankful the solution was something that could be addressed at all. My 10G Ubiquiti switch won’t allow HDHomeRun devices to directly connect at all, since they have no support for Fast Ethernet devices. I have to connect an interim 1G switch to the 10G switch, and then my HDHomeRuns to the 1G switch in order to get them on the network. This is not a DHCP issue, it is an actual physical limitation of the 10G switch.

A part of me does understand why the HDHomeRuns are only 100Mbps devices, but then again another part of me really wishes SiliconDust wouldn’t have been so cheap so as to save $.06 vs including a proper 1Gbps port on their devices, especially on the new 4K units. This is just a headache I guess I have to live with, and is probably my greatest annoyance with the product.

jasonl
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by jasonl »

By the time you get to final retail price of a device, it's a difference of several dollars, not 6 cents. SoCs that have gigabit ethernet built in are not common and are significantly more expensive than the one SD is using. The other option is to use a SoC that has USB 3 or PCIe and a separate ethernet chip, but that adds cost for the better SoC, cost for the ethernet chip, cost for the support components it requires (resistors, capacitors, etc.), and probably a larger PCB and a larger case to hold it. Then there's the cost of engineering time in rewriting everything to actually get the system booting on a new SoC, which can easily be weeks of work.

csdesigns
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by csdesigns »

jasonl wrote: Sat Feb 20, 2021 1:06 pm By the time you get to final retail price of a device, it's a difference of several dollars, not 6 cents.
Fair enough, but admittedly, I was being a bit tongue-in-check there. :D

As I stated, I 'get' why there is only a FE NIC on these devices. While there hypothetically is a chance that at some point, in some market, there will be 4x UHD channels all broadcasting over 25mbps which some customer will want to simultaneously record/view, I seriously doubt we'll ever see that day, thus the physical limit of the port isn't going to be a factor. But it is a factor as more and more 10G home networks are stood up, and device interoperability is an issue. I don't really fault the SD engineers for not foreseeing this though – it's certainly a first-world kind of problem.

jasonl
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by jasonl »

Even if some market did that (which will never happen, because ATSC 3 stations will end up basically upgrading their legacy ATSC broadcasts to a single 1080p of the main network and 4-5 720p subchannels), the 4K device is 2+2 tuners so you'd still top out at 25+25+15+15 = 80Mb/s or whatever, which should be doable. Also, there's no reason a switch can't support everything from 10BASE-T to 10GBASE-T, so even someone who decides to upgrade to get 10G between their NAS and their main PC should still be able to use it unless the switch is just a piece of crap. There is ample reason for switch manufacturers to support slower speeds, as there are literally billions of IoT devices out there that are only 100Mbit, including most security cameras.

djp952
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by djp952 »

All true, but IMO there are also a great deal of consumer/prosumer (and even enterprise) switches out there that completely fall apart when a 100BASE-T device is plugged into an otherwise 1000BASE-T topology. I've found that there is a happy medium of sorts -- using a low-end core switch is bad, using a high-end 'managed' core switch is also bad if you don't or are unable to configure it properly, finding the middle-end core switch that "just works" can be elusive for a lot of people. They also seem to think that adding more switches to expand a network is a good idea. (It can be, but you really won't know until you try!)

I'm personally in the camp of WTH on all the 100BASE-T decisions, especially for the abandoned Prime-6 device. As a consumer I would absolutely pay "several dollars" more to have 1000BASE-T be available on these devices, and let said devices auto-negotiate with the network they are attached to at that rate.

Most consumers/prosumers don't understand the limitations of a network topology that relies on having a number of consumer-grade network switches all wired together as if that is a proper "network". Supporting 1000BASE-T when only 100BASE-T (Full Duplex) is required gives these users the wiggle room they need to overcome any uninformed decisions they may have made. Normal people shouldn't need to concern themselves with such things. It really should "just work" for them.

SiliconDust cannot control it's end user networking choices, nor can it predict the future, this is understood. My hang up is understanding why SD isn't properly positioning itself technologically for either the "as-is" or "to-be" state of Home Networking and has instead apparently doubled-down on the "as-was" state. A lack of 1000BASE-T (Gigabit Internet) support in 2021 when prior device(s) actually support this is, to me, a show-stopper. I intend to milk my existing HDHomeRun PRIME devices as long as I possibly can.

nickk
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by nickk »

First, all switches should (should) support 10baseT and 100baseTX. It is not uncommon for GigE NICs to have a power save mode where they switch to 10baseT so they can listen for wake-on-lan packets.

Second, there are no topology considerations due to the HDHomeRun being 100baseTX as they don't receive data at any meaningful rate. The HDHomeRun won't slow down anything on the network being 100baseTX. We recommend using GigE switches to avoid bottlenecks to the recording server or between switches.

csdesigns
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by csdesigns »

jasonl wrote: Tue Feb 23, 2021 7:32 pm Even if some market did that (which will never happen, because ATSC 3 stations will end up basically upgrading their legacy ATSC broadcasts to a single 1080p of the main network and 4-5 720p subchannels), the 4K device is 2+2 tuners so you'd still top out at 25+25+15+15 = 80Mb/s or whatever, which should be doable. Also, there's no reason a switch can't support everything from 10BASE-T to 10GBASE-T, so even someone who decides to upgrade to get 10G between their NAS and their main PC should still be able to use it unless the switch is just a piece of crap. There is ample reason for switch manufacturers to support slower speeds, as there are literally billions of IoT devices out there that are only 100Mbit, including most security cameras.
Ok, let's not get into whether or not this will ever happen, because as I already stated, it will not. But if we want to play with numbers and hypotheticals (which isn't my issue), then hypothetically, ATSC 3.0 can command a maximum capacity of 57Mbps per frequency (again, I don't think we'll ever see anything like this in the reasonable lifespan of this product, but...). So, theoretically tuning into two ATSC 3.0 frequencies simultaneously would be impossible over FE if two channels in an area decided to use this full bandwidth. Even if things stay similar to as they have launched, where most frequencies are only using ~26Mbps, and we get to a point one day where ATSC 3.0 is so ubiquitous (no pun intended) and profitable that all stations are running their own towers again (ain't happening), then 26Mbps x 2 + 19.4Mbps (max of ATSC 1.0, since in this hypothetical what is good for the goose is good for the gander) x 2 = >90Mbps, which is cutting it pretty tight there. I'll reiterate that I know this is not going to happen at any point within the near future, but it's fun to postulate.

Regarding your comments on the switches though, unfortunately, you're a bit off-base there. There are plenty of instances, in all of the switch markets (consumer / prosumer / enthusiast / professional / enterprise) where higher-rated switches don't operate nicely with lower-rated devices. While I don't think of Ubiquiti as a maker of enterprise-class switches, they certainly don't make crap products either. And from what I have read, their 10G switches aren't the only ones which can't properly negotiate with FE devices. So either all of these other switches are crap, or this is potentially a real issue (even if the number of customers who will run into this is a really small portion of the marker atm). While I agree that switch manufacturers have ample reasons to support the litany of FE-only IoT devices out there with their switch, this has unfortunately not been a priority. It's a shame the situation is what it is, but thankfully there are inexpensive workarounds (the biggest hindrance to all this is having to plug in another power supply).

csdesigns
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by csdesigns »

nickk wrote: Tue Feb 23, 2021 11:14 pm Second, there are no topology considerations due to the HDHomeRun being 100baseTX as they don't receive data at any meaningful rate. The HDHomeRun won't slow down anything on the network being 100baseTX. We recommend using GigE switches to avoid bottlenecks to the recording server or between switches.
Nick, my concern has never been about whether or not a user will 'saturate' the topology of a network because the HDHomerun device is FE. The whole issue at hand, which admittedly seems to have gotten lost a bit here, is that while "should" is a nice thing to have, it is not what we actually have. Simply put, I've run into an issue where none of my HDHomerun devices will directly connect to my 10G switch (either via SFP module or on-board copper). I have read similar reports of other users of other 10G switches with other FE-rated devices having similar issues, so this is not an isolated issue. That's all I am trying to convey. Hopefully your engineers will take this into consideration when building your future products. I have 5 HDHR devices already. I'll probably buy whatever the next major model release is as well. I will just hope that this situation is resolved by the time that comes.

lukejenkins
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by lukejenkins »

Network Engineer at a .edu by day here. +1 on having to deal with the latest gen switching gear (mostly Cisco) both on our campus and in the datacenter that doesn’t play well with 10meg devices or even some 100meg devices. We’ve had to start putting in work arounds like dumb 5 port gige switches on scada gear and making sure to include some 1gig/non-mgig ports in every closet.

Oh and don’t even get me started on the pain that is EEE.

Happy to chat more if you’d like some specifics,but please include gigabit on all devices still in the requirements phase, especially the rack mount line.

though
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by though »

FYI my HDHR5-4K feeds directly to a US-8-60W that feeds a US-24-250W. I have no issues whatsoever.

alikaz
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Re: Interoperability issue with HDHomerun4K and Ubiquiti switches

Post by alikaz »

Hmm I've got mine running on a US-8-60W and I've never had this problem, but I'm running firmware that's probably a month old? OP did say it was new firmware that caused it, makes me want to stick on the version I'm on now hehe

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