Mailing List Archive

HDHomeRun tuners and network switches
I'm trying to fix some issues with mythtv having breakups in the signal
that could be a number of things like antenna placement, original signal
quality, or networking issues.

My production mythtv backend is using a WinTV quadHD PCI3 tuner card and I
generally don't have issues with those recordings. It's always the
HDHomerun tuners that are connected to a test backend.

I watch either backend using FireTV 4K sticks or Nvidia Shield TV with the
mythfrontend and Leanfront apps. So lots of networking potential problem
areas. All of the streaming devices and backends are wired with either
CAT5e or CAT 6 cables.

I have at the top of the tree a TP Link AX50 WiFi 6 AP/router. Each of the
ports are connected to 8-port GbE switches in other cabinets or rooms.

The problem got bad enough this morning that I decided to dig deeper into
the situation. While watching the recorded morning news, the picture kept
pixelating with lost sound a lot more than is tolerable. I checked the
HDHR tuner with their signal app and the quality and stability of the
signal looked great.

The Shield TV and mythtv test backend that was recording the program are on
the same switch 1 in a cabinet and the HDHR tuner was connected to another
switch in another cabinet. So I moved the cables around so that one of the
GbE switches had the HDHR, mythtv backend, and the cable running to the
cabinet with a switch for the streaming devices. This seems to fix the
issue. However if the cable going to the streaming devices is plugged into
the switch above then I have issues. An attempt at a schematic below to
make it clearer.

AP-router-----> switch 1 in closet (test mythtv-backend, HDHR tuner)
|-----> switch 2 in closet
|-----> switch 3 in cabinet with streaming devices (FireTV,
Shield)

The above has the most break ups when watching

However, moving the cable leading to switch 3 from the AP/router to switch
1 seems to work best.

Does this make sense or point to a problem?

Jim A
Re: HDHomeRun tuners and network switches [ In reply to ]
Hoi James,

Thursday, January 20, 2022, 2:51:31 PM, you wrote:

> I'm trying to fix some issues with mythtv having breakups in the
> signal that could be a number of things like antenna placement,
> original signal quality, or networking issues.


> My production mythtv backend is using a WinTV quadHD PCI3 tuner
> card and I generally don't have issues with those recordings.  It's
> always the HDHomerun tuners that are connected to a test backend.


> I watch either backend using FireTV 4K sticks or Nvidia Shield TV
> with the mythfrontend and Leanfront apps. So lots of networking
> potential problem areas.  All of the streaming devices and backends
> are wired with either CAT5e or CAT 6 cables.


> I have at the top of the tree a TP Link AX50 WiFi 6 AP/router. 
> Each of the ports are connected to 8-port GbE switches in other cabinets or rooms.


> The problem got bad enough this morning that I decided to dig
> deeper into the situation.  While watching the recorded morning
> news, the picture kept pixelating with lost sound a lot more than is
> tolerable.  I checked the HDHR tuner with their signal app and the
> quality and stability of the signal looked great.


> The Shield TV and mythtv test backend that was recording the
> program are on the same switch 1 in a cabinet and the HDHR tuner was
> connected to another switch in another cabinet.  So I moved the
> cables around so that one of the GbE switches had the HDHR, mythtv
> backend, and the cable running to the cabinet with a switch for the
> streaming devices. This seems to fix the issue.  However if the
> cable going to the streaming devices is plugged into the switch
> above then I have issues. An attempt at a schematic below to make it clearer.


AP-router----->> switch 1 in closet (test mythtv-backend, HDHR tuner)
>                |-----> switch 2 in closet
>                |-----> switch 3 in cabinet with streaming devices (FireTV, Shield)


> The above has the most break ups when watching


> However, moving the cable leading to switch 3 from the AP/router to switch 1 seems to work best.


> Does this make sense or point to a problem?


> Jim A

This is probably a recording issue. The suspects are:
1. The hdhr power supply
2. The available network bandwidth. Try connecting to a dedicated nic
on the backend. This however requirs you to setup a dhcp server on
that backend
3. The available disk bandwidth

To check if it is not a playback issue, try playback on the backend
or a frontend connected to the same switch as the backend while there
is no recording activity. However bad playback connection would give
stuttering not pixelation.







Tot mails,
Hika mailto:hikavdh@gmail.com

"Zonder hoop kun je niet leven
Zonder leven is er geen hoop
Het eeuwige dilemma
Zeker als je hoop moet vernietigen om te kunnen overleven!"

De lerende Mens

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Re: HDHomeRun tuners and network switches [ In reply to ]
On 1/20/22 8:51 AM, James Abernathy wrote:
> I'm trying to fix some issues with mythtv having breakups in the
> signal that could be a number of things like antenna placement,
> original signal quality, or networking issues.
>
> My production mythtv backend is using a WinTV quadHD PCI3 tuner card
> and I generally don't have issues with those recordings.  It's always
> the HDHomerun tuners that are connected to a test backend.
>
> I watch either backend using FireTV 4K sticks or Nvidia Shield TV with
> the mythfrontend and Leanfront apps. So lots of networking potential
> problem areas.  All of the streaming devices and backends are wired
> with either CAT5e or CAT 6 cables.
>
> I have at the top of the tree a TP Link AX50 WiFi 6 AP/router.  Each
> of the ports are connected to 8-port GbE switches in other cabinets or
> rooms.
>
> The problem got bad enough this morning that I decided to dig deeper
> into the situation.  While watching the recorded morning news, the
> picture kept pixelating with lost sound a lot more than is tolerable. 
> I checked the HDHR tuner with their signal app and the quality and
> stability of the signal looked great.
>
> The Shield TV and mythtv test backend that was recording the program
> are on the same switch 1 in a cabinet and the HDHR tuner was connected
> to another switch in another cabinet.  So I moved the cables around so
> that one of the GbE switches had the HDHR, mythtv backend, and the
> cable running to the cabinet with a switch for the streaming devices.
> This seems to fix the issue.  However if the cable going to the
> streaming devices is plugged into the switch above then I have issues.
> An attempt at a schematic below to make it clearer.
>
> AP-router-----> switch 1 in closet (test mythtv-backend, HDHR tuner)
>                |-----> switch 2 in closet
>                |-----> switch 3 in cabinet with streaming devices
> (FireTV, Shield)
>
> The above has the most break ups when watching
>
> However, moving the cable leading to switch 3 from the AP/router to
> switch 1 seems to work best.
>
> Does this make sense or point to a problem?
>
> Jim A
>
>
I had this problem a few years back with the HD Homerun Prime.
Pixellation every minute or so. After lots of messing around it turned
out that if the signal from the HDHomerun Prime to the backend traveled
through the router, sometimes a UDP message was dropped. I forget the
router brand. Reconfiguring the network so that the signal only traveled
through a switch solved it. It looks like this does not happen in your
case, maybe the switch between the hd homerun and the backend is the
problem.

I verified it with this test, from the manual for the hd homerun prime,
see below. When the signal passed through the router, occasional errors
were reported in the dots. Without the router between there were no errors.

*Saving a stream:**
*
The hdhomerun_config command can be used to automate the process of
saving to the local
filesystem:
format: hdhomerun_config <id> save /tuner<n> <filename>
eg:     hdhomerun_config FFFFFFFF save /tuner0 capture.ts
While saving the stream, a single period “.” will be displayed every
second. Additionally, as of the
20080609 release, the hdhomerun_config will detect reception and network
errors, replacing the
“.” with an alternative character to indicate the problem.
Example output:
............n...............................n..........ts..........
-- Video statistics --
23323 packets recieved, 2 network errors, 1 transport errors, 1 sequence
errors

*Advanced:* A filename of “null” indicates no file should be created,
allowing the use of the save
command as a diagnostic tool.

Peter
Re: HDHomeRun tuners and network switches [ In reply to ]
On Thu, 2022-01-20 at 08:51 -0500, James Abernathy wrote:
> I'm trying to fix some issues with mythtv having breakups in the
> signal that could be a number of things like antenna placement,
> original signal quality, or networking issues.
>
> My production mythtv backend is using a WinTV quadHD PCI3 tuner card
> and I generally don't have issues with those recordings.  It's always
> the HDHomerun tuners that are connected to a test backend.
>
> I watch either backend using FireTV 4K sticks or Nvidia Shield TV
> with the mythfrontend and Leanfront apps. So lots of
> networking potential problem areas.  All of the streaming devices and
> backends are wired with either CAT5e or CAT 6 cables.
>
> I have at the top of the tree a TP Link AX50 WiFi 6 AP/router.  Each
> of the ports are connected to 8-port GbE switches in other cabinets
> or rooms.
>
> The problem got bad enough this morning that I decided to dig deeper
> into the situation.  While watching the recorded morning news, the
> picture kept pixelating with lost sound a lot more than is
> tolerable.  I checked the HDHR tuner with their signal app and the
> quality and stability of the signal looked great.
>
> The Shield TV and mythtv test backend that was recording the program
> are on the same switch 1 in a cabinet and the HDHR tuner was
> connected to another switch in another cabinet.  So I moved the
> cables around so that one of the GbE switches had the HDHR, mythtv
> backend, and the cable running to the cabinet with a switch for the
> streaming devices. This seems to fix the issue.  However if the cable
> going to the streaming devices is plugged into the switch above then
> I have issues. An attempt at a schematic below to make it clearer.
>
> AP-router-----> switch 1 in closet (test mythtv-backend, HDHR tuner)
>                |-----> switch 2 in closet
>                |-----> switch 3 in cabinet with streaming devices
> (FireTV, Shield)
>
> The above has the most break ups when watching
>
> However, moving the cable leading to switch 3 from the AP/router to
> switch 1 seems to work best.
>
> Does this make sense or point to a problem?
>
> Jim A
>
>
>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users@mythtv.org
> http://email.mg.glenb.net/c/eJxNjs0KwjAQhJ-mvVl2N2lMDjl48T02P_2BJJUmCr69VQSFucw3MzDB-onDKPvVakeCHAYBIwUvUUSO4OKoQIJhoxA1kgAePOeYOglzisUNJbZ-sYYI2Ixak2QkCGhAgUYXhFJn73yf7NLarROXjq6H0lpbHfKzLe0xbPt8oMxryly-4Vqm7Q0_jdO9xr32u_23x4Pf_gX3JD8u
> http://email.mg.glenb.net/c/eJxFjTsOwjAQBU8Td1jr9Udx4YKGCs4Q-bMkFkmAZAPi9kSiQHrVaEavhHyNxRpRQ5tQY1JFg8WSjdIUCRJZBwZ89E6pVqGGKHOcaGwM9CPNSc7EYggOITmfLGbwCNZZ7VL0qWTMPoL3YgwD86PRxwZP-971VuX04YFf8r70O7nEOta578515Y64PjdiJrGEn3XYVlrW_fUffQFWUzuE
> MythTV Forums: http://email.mg.glenb.net/c/eJxFjDEOwjAMRU_TbESxnZR2yMDCPRzHaZHagtIUidtTiQHpL09P7-cohXPw5hGHhIQJMrmAWTyQsrqkoXfejTz2AAMgObbCqy6dd9OiW7KbNjPHPpxFuRISFyYVFuCAAohCg45qlji39to7unV4P1ee9Vjt-mlze9tnnUyNP7gcu9b9vP-7L6PjM4w
you can contact silicondust and set up debugging at the hdhr, they will
tell if your problem is your home network or the signal/hdhr. Sounds
like the box and signal is OK by what your describe.

Recently I had a similar problem where my recordings had
breakups/pixelation and my hdhrconfig gui the signal looked fine. I use
a wireless bridge to push from the hdhr to my server, with one switch
in its path. I separate out my wifi from my router and use a separate
dumb ap for wifi. So it is hdhr ethernet to wifi bridge unit (tp-link
c7 - openwrt) wireless to belkin3200ax then wired to Netgear gaming
switch then wired to backend recorder. I use a programmable netgear
gaming switch. Swapping out the ap for the new 3200ax solved my problem
and it is perfect again. The shields I use mostly for viewing both are
switches that feed from the netgear switch. From what you describe your
issue is one of the switches I would guess
Re: HDHomeRun tuners and network switches [ In reply to ]
On 20/01/2022 14:24, Peter Bennett wrote:
>
> On 1/20/22 8:51 AM, James Abernathy wrote:
>> I'm trying to fix some issues with mythtv having breakups in the signal that could be a number of
>> things like antenna placement, original signal quality, or networking issues.
>>
>> My production mythtv backend is using a WinTV quadHD PCI3 tuner card and I generally don't have
>> issues with those recordings.  It's always the HDHomerun tuners that are connected to a test backend.
>>
>> I watch either backend using FireTV 4K sticks or Nvidia Shield TV with the mythfrontend and
>> Leanfront apps. So lots of networking potential problem areas.  All of the streaming devices and
>> backends are wired with either CAT5e or CAT 6 cables.
>>
>> I have at the top of the tree a TP Link AX50 WiFi 6 AP/router.  Each of the ports are connected to
>> 8-port GbE switches in other cabinets or rooms.
>>
>> The problem got bad enough this morning that I decided to dig deeper into the situation.  While
>> watching the recorded morning news, the picture kept pixelating with lost sound a lot more than is
>> tolerable. I checked the HDHR tuner with their signal app and the quality and stability of the
>> signal looked great.
>>
>> The Shield TV and mythtv test backend that was recording the program are on the same switch 1 in a
>> cabinet and the HDHR tuner was connected to another switch in another cabinet.  So I moved the
>> cables around so that one of the GbE switches had the HDHR, mythtv backend, and the cable running
>> to the cabinet with a switch for the streaming devices. This seems to fix the issue.  However if
>> the cable going to the streaming devices is plugged into the switch above then I have issues. An
>> attempt at a schematic below to make it clearer.
>>
>> AP-router-----> switch 1 in closet (test mythtv-backend, HDHR tuner)
>>                |-----> switch 2 in closet
>>                |-----> switch 3 in cabinet with streaming devices (FireTV, Shield)
>>
>> The above has the most break ups when watching
>>
>> However, moving the cable leading to switch 3 from the AP/router to switch 1 seems to work best.
>>
>> Does this make sense or point to a problem?
>>
>> Jim A
>>
>>
> I had this problem a few years back with the HD Homerun Prime. Pixellation every minute or so. After
> lots of messing around it turned out that if the signal from the HDHomerun Prime to the backend
> traveled through the router, sometimes a UDP message was dropped. I forget the router brand.
> Reconfiguring the network so that the signal only traveled through a switch solved it. It looks like
> this does not happen in your case, maybe the switch between the hd homerun and the backend is the
> problem.
>
> I verified it with this test, from the manual for the hd homerun prime, see below. When the signal
> passed through the router, occasional errors were reported in the dots. Without the router between
> there were no errors.
>
> *Saving a stream:**
> *
> The hdhomerun_config command can be used to automate the process of saving to the local
> filesystem:
> format: hdhomerun_config <id> save /tuner<n> <filename>
> eg:     hdhomerun_config FFFFFFFF save /tuner0 capture.ts
> While saving the stream, a single period “.” will be displayed every second. Additionally, as of the
> 20080609 release, the hdhomerun_config will detect reception and network errors, replacing the
> “.” with an alternative character to indicate the problem.
> Example output:
> ............n...............................n..........ts..........
> -- Video statistics --
> 23323 packets recieved, 2 network errors, 1 transport errors, 1 sequence errors
>
> *Advanced:* A filename of “null” indicates no file should be created, allowing the use of the save
> command as a diagnostic tool.
>
While I do not use a TP-Link switch as my router, I do have a TP-Link dedicated AP on my network and
all my switches are also TP-Link. They are reliable enough and, more importantly, affordable.

Firstly, all the switches work fine. None are new but all have done service for many years. Two are
unmanaged and the rest are "easy" managed. No problems (so far) with power supplies.

However, one of them has the AP plugged into it and that does have quirks. Due to the fact it wants
to talk to others of its kind, and maybe participate in a network such as one might find in an
office block, hotel or factory, it sends out Level 2 queries all the time and I can find no way to
stop them.

To stop it from flooding the whole network it has its own dedicated switch port and VLAN and is
firewalled off except for valid packets.

I do not have experience with your specific switch/router but perhaps it is trying to do something
similar. Those packets could easily cause the loss of some UDP traffic.

--

Mike Perkins

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Re: HDHomeRun tuners and network switches [ In reply to ]
On 1/20/22 7:51 AM, James Abernathy wrote:
> I'm trying to fix some issues with mythtv having breakups in the
> signal that could be a number of things like antenna placement,
> original signal quality, or networking issues.
>
> My production mythtv backend is using a WinTV quadHD PCI3 tuner card
> and I generally don't have issues with those recordings.  It's always
> the HDHomerun tuners that are connected to a test backend.
>
> I watch either backend using FireTV 4K sticks or Nvidia Shield TV with
> the mythfrontend and Leanfront apps. So lots of networking potential
> problem areas.  All of the streaming devices and backends are wired
> with either CAT5e or CAT 6 cables.
>
> I have at the top of the tree a TP Link AX50 WiFi 6 AP/router.  Each
> of the ports are connected to 8-port GbE switches in other cabinets or
> rooms.
>
> The problem got bad enough this morning that I decided to dig deeper
> into the situation.  While watching the recorded morning news, the
> picture kept pixelating with lost sound a lot more than is tolerable. 
> I checked the HDHR tuner with their signal app and the quality and
> stability of the signal looked great.
>
> The Shield TV and mythtv test backend that was recording the program
> are on the same switch 1 in a cabinet and the HDHR tuner was connected
> to another switch in another cabinet.  So I moved the cables around so
> that one of the GbE switches had the HDHR, mythtv backend, and the
> cable running to the cabinet with a switch for the streaming devices.
> This seems to fix the issue.  However if the cable going to the
> streaming devices is plugged into the switch above then I have issues.
> An attempt at a schematic below to make it clearer.
>
> AP-router-----> switch 1 in closet (test mythtv-backend, HDHR tuner)
>                |-----> switch 2 in closet
>                |-----> switch 3 in cabinet with streaming devices
> (FireTV, Shield)
>
> The above has the most break ups when watching
>
> However, moving the cable leading to switch 3 from the AP/router to
> switch 1 seems to work best.
>
> Does this make sense or point to a problem?
>

Maybe the pixelization is caused by a network issue.

A problem that moves around when network cables are rearranged might be
caused by a marginal CatX cable or a bad switch port.

I've experienced two scenarios with CatX cables: (1) the switch ports
connected to the cable negotiated to 100 Mbps or 10 Mbps instead of the
expected 1 Gbps or (2) the switch ports negotiated to 1 Gbps but a high
error rate was caused by an inadequate cable (e.g., a long Cat5 cable),
an incorrectly terminated cable, or interference. If the cable is a path
to/from another switch, either scenario can have the effect of limiting
the network bandwidth that's handled by one of the switches. If you have
spare Cat5e or Cat6 cables on hand, see if the issue goes away when you
replace a cable.

Regarding interference, make sure that your CatX cables aren't too close
to AC in-wall wiring, AC power cables, or interference-generating
appliances such as fluorescent lights. Lengthy CatX cable runs that are
parallel to nearby AC wiring can be a particular problem. If you have a
very long Cat5x cable, consider replacing it with Cat6 which is designed
to be less sensitive to interference compared with Cat5x. If you
discover an interference issue that won't go away, consider shielded
Cat6 cables but they will be effective only if all Ethernet jacks on the
path are grounded (i.e., a metallic tab is present on the two sides of
the switch port).

To check out a possible switch port issue, try moving each end of the
cable to another port on the same switch. Do this one end at a time.
Note that it's not super-difficult for an incorrectly inserted cable
terminator (plug) to damage the tiny little wires at the bottom of the
switch port.

Dave
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Re: HDHomeRun tuners and network switches [ In reply to ]
On Thu, Jan 20, 2022 at 9:25 AM Peter Bennett <pb.mythtv@gmail.com> wrote:

>
> On 1/20/22 8:51 AM, James Abernathy wrote:
>
> I'm trying to fix some issues with mythtv having breakups in the signal
> that could be a number of things like antenna placement, original signal
> quality, or networking issues.
>
> My production mythtv backend is using a WinTV quadHD PCI3 tuner card and I
> generally don't have issues with those recordings. It's always the
> HDHomerun tuners that are connected to a test backend.
>
> I watch either backend using FireTV 4K sticks or Nvidia Shield TV with the
> mythfrontend and Leanfront apps. So lots of networking potential problem
> areas. All of the streaming devices and backends are wired with either
> CAT5e or CAT 6 cables.
>
> I have at the top of the tree a TP Link AX50 WiFi 6 AP/router. Each of
> the ports are connected to 8-port GbE switches in other cabinets or rooms.
>
> The problem got bad enough this morning that I decided to dig deeper into
> the situation. While watching the recorded morning news, the picture kept
> pixelating with lost sound a lot more than is tolerable. I checked the
> HDHR tuner with their signal app and the quality and stability of the
> signal looked great.
>
> The Shield TV and mythtv test backend that was recording the program are
> on the same switch 1 in a cabinet and the HDHR tuner was connected to
> another switch in another cabinet. So I moved the cables around so that
> one of the GbE switches had the HDHR, mythtv backend, and the cable running
> to the cabinet with a switch for the streaming devices. This seems to fix
> the issue. However if the cable going to the streaming devices is plugged
> into the switch above then I have issues. An attempt at a schematic below
> to make it clearer.
>
> AP-router-----> switch 1 in closet (test mythtv-backend, HDHR tuner)
> |-----> switch 2 in closet
> |-----> switch 3 in cabinet with streaming devices (FireTV,
> Shield)
>
> The above has the most break ups when watching
>
> However, moving the cable leading to switch 3 from the AP/router to switch
> 1 seems to work best.
>
> Does this make sense or point to a problem?
>
> Jim A
>
>
> I had this problem a few years back with the HD Homerun Prime. Pixellation
> every minute or so. After lots of messing around it turned out that if the
> signal from the HDHomerun Prime to the backend traveled through the router,
> sometimes a UDP message was dropped. I forget the router brand.
> Reconfiguring the network so that the signal only traveled through a switch
> solved it. It looks like this does not happen in your case, maybe the
> switch between the hd homerun and the backend is the problem.
>
> I verified it with this test, from the manual for the hd homerun prime,
> see below. When the signal passed through the router, occasional errors
> were reported in the dots. Without the router between there were no errors.
>
> *Saving a stream:*
>
> The hdhomerun_config command can be used to automate the process of saving
> to the local
> filesystem:
> format: hdhomerun_config <id> save /tuner<n> <filename>
> eg: hdhomerun_config FFFFFFFF save /tuner0 capture.ts
> While saving the stream, a single period “.” will be displayed every
> second. Additionally, as of the
> 20080609 release, the hdhomerun_config will detect reception and network
> errors, replacing the
> “.” with an alternative character to indicate the problem.
> Example output:
> ............n...............................n..........ts..........
> -- Video statistics --
> 23323 packets recieved, 2 network errors, 1 transport errors, 1 sequence
> errors
>
> *Advanced:* A filename of “null” indicates no file should be created,
> allowing the use of the save
> command as a diagnostic tool.
>
> Peter
>
So in your case and maybe mine if the HDHR tuners have to go back through
the AP/router to get to the Mythtv backend that is where you could have
issues. That would explain why the same streaming devices can process
playback from the production backend going through the AP/router without
issue because the production tuner is an internal PCIe card.
Re: HDHomeRun tuners and network switches [ In reply to ]
>
>
> The above has the most break ups when watching
>
> However, moving the cable leading to switch 3 from the AP/router to switch 1 seems to work best.
>
> Does this make sense or point to a problem?
>
> Jim A
>
>
>

I use the hdhomerun_config_gui utility and watch the meters that are displayed. Those meters will tell you if you are having antenna problems . If the green bars stay consistent, then sounds like a network problem as discussed..

I also use a different variation of the hdhr config command line to dump the same info as seen in the guy above as follows:

hdhr=<hdhr_id>

hdhomerun_config $hdhr get /tuner0/status

When the above is looped, you will see drops if there are problems as you would with the gui version above.

Someone also mentioned the power supply, and I have had to replace those when things got weird.

Regards


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Re: HDHomeRun tuners and network switches [ In reply to ]
On Thu, Jan 20, 2022 at 10:44 AM Jay Harbeston <jharbestonus@gmail.com>
wrote:

> >
> >
> > The above has the most break ups when watching
> >
> > However, moving the cable leading to switch 3 from the AP/router to
> switch 1 seems to work best.
> >
> > Does this make sense or point to a problem?
> >
> > Jim A
> >
> >
> >
>
> I use the hdhomerun_config_gui utility and watch the meters that are
> displayed. Those meters will tell you if you are having antenna problems .
> If the green bars stay consistent, then sounds like a network problem as
> discussed..
>
> I also use a different variation of the hdhr config command line to dump
> the same info as seen in the guy above as follows:
>
> hdhr=<hdhr_id>
>
> hdhomerun_config $hdhr get /tuner0/status
>
> When the above is looped, you will see drops if there are problems as you
> would with the gui version above.
>
> Someone also mentioned the power supply, and I have had to replace those
> when things got weird.
>
> Regards
>

Thanks for all the suggestions. I used the hdhomerun_config to capture
some video with no errors of any kind now that I kept the tuners from
routing through the AP/router. I think I'm going to move everything out of
the AP/router except the one cable to the first switch.

JIm A
Re: HDHomeRun tuners and network switches [ In reply to ]
On Thu, 20 Jan 2022 10:59:55 -0500, you wrote:

>Thanks for all the suggestions. I used the hdhomerun_config to capture
>some video with no errors of any kind now that I kept the tuners from
>routing through the AP/router. I think I'm going to move everything out of
>the AP/router except the one cable to the first switch.
>
>JIm A

I do not know about the AX50, so I do not know how its Ethernet LAN
ports work. There are basically two different ways that routers
handle LAN ports. One way has the LAN ports connected to the router
hardware individually and all traffic between the LAN ports goes via
the routing hardware or the router CPU (or both). This setup is very
useful if you want separate LANs with separate routing for each LAN,
but very bad if you want two or more of the LAN ports to be on the
same subnet (ie bridged together).

Routers are very bad at bridging - that is a function best left to
switches. So packets supposedly on the same subnet that have to
traverse the router to get to a different LAN port will often have low
throughput, as the CPU needs to examine and route each packet, and
router CPUs are not normally very fast. Routers do high speed routing
on their dedicated router hardware, and packets that need to be
examined by the CPU will have low throughput. Low throughput = low
bandwidth. Low bandwidth compared to the 1 gigabit/s of the LAN port
means that if there is too much traffic, packets will be dropped to
reduce the traffic down to the amount that can actually be routed
between the LAN ports. This is a likely scenario for your setup - UDP
packets traversing the router between LAN ports are too much for the
router CPU to handle and are not being routed by the dedicated
hardware as router hardware usually does not do bridging. So some UDP
packets get dropped. CPU routed packets on my old ERLite router had
only about 150-200 Mbit/s bandwidth available once I had all my
firewall rules installed. Packets routed on its dedicated routing
hardware had 1 gigabit/s bandwidth.

The plus side of this LAN port configuration is that if you really are
routing between the LAN ports rather than bridging (ie each LAN port
has a different subnet on it), then you can get full gigabit routing
between all the ports (including the CPU/router hardware port and
access via that to the WAN port). That assumes that you only use the
routing features that are handled on the dedicated routing hardware.
QoS, for example, will usually require the packets to be routed via
the CPU.

The other way of organising router LAN ports has all the LAN ports on
a separate internal hardware switch, and also on that switch is an
internal Ethernet port to the router hardware and/or the router CPU.
Sometimes there is a separate port for the CPU and the dedicated
router hardware. This separate switch works exactly the same as a
normal external Ethernet switch. It is usually moderately intelligent
- it has VLAN capabilities. You can configure the switch VLANs so
some of the LAN ports just connect to each other over a VLAN
(bridged), or there can be a VLAN that connects them to the Ethernet
port to the router, or some combination of VLANs. With this sort of
LAN port configuration, if you have several of your LAN ports on the
same subnet, you can just configure them to be bridged on the same
VLAN and there will not be any bandwidth problems with the bridged
packets. The bridged packets are handled entirely in the switch
hardware and are never seen by the CPU or router hardware. The
downside of this sort of LAN port configuration is that there is
contention between the LAN ports for the CPU/router hardware port when
packets between the LAN ports actually need to be routed instead of
bridged. You potentially have say 4 LAN ports wanting all their
traffic to be routed via one single gigabit port to the CPU/router
hardware. In some routers using switched LAN ports, the WAN port can
also be on the switch, causing contention between WAN packets and LAN
packets for access to the CPU.

Really good routers that use switched LAN ports solve the problem by
having a higher speed on the CPU/router hardware port, so if there are
4 x 1 gigabit/s LAN ports, the CPU/router hardware port will be 4
gigabits/s. Such routers are usually far beyond the means of home
users to ever contemplate buying.

So what I recommend to people buying a router is to find out which
sort of router it is and whether that is actually the sort they want,
depending on what they want their LAN ports to be used for. I have
Ubiquity ER4 router, which has separate LAN ports. In the Ubiquiti
routers, there are others (such as the ER-X) which have switched LAN
ports, and some that have a mixture (such as one separate LAN port and
5 switched LAN ports). If you have a small network where you do not
need any more LAN ports than are switched LAN ports on the router,
then getting a router with switched LAN ports saves the need to buy a
separate switch. But if your needs are larger than that, I think it
is best to get a router with non-switched LAN ports and also get
yourself a decent switch or two to go with it. Do all the routing on
the router and all the bridging on the switches. I have a Ubiquiti
ES-24 Lite switch to go with my ER-4. It is a full commercial grade
switch with all the features I might ever need in a switch, except for
POE. I also have a simple unmanaged 5 port switch to use whenever I
have only one Ethernet connection at a location and need more - I can
use it until I get a new cable installed to that location from my
ES-24 main switch.
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Re: HDHomeRun tuners and network switches [ In reply to ]
On 1/21/22 5:11 AM, Stephen Worthington wrote:
> On Thu, 20 Jan 2022 10:59:55 -0500, you wrote:
>
>> Thanks for all the suggestions. I used the hdhomerun_config to capture
>> some video with no errors of any kind now that I kept the tuners from
>> routing through the AP/router. I think I'm going to move everything out of
>> the AP/router except the one cable to the first switch.
>>
>> JIm A
> I do not know about the AX50, so I do not know how its Ethernet LAN
> ports work. There are basically two different ways that routers
> handle LAN ports. One way has the LAN ports connected to the router
> hardware individually and all traffic between the LAN ports goes via
> the routing hardware or the router CPU (or both). This setup is very
> useful if you want separate LANs with separate routing for each LAN,
> but very bad if you want two or more of the LAN ports to be on the
> same subnet (ie bridged together).
>
> Routers are very bad at bridging - that is a function best left to
> switches. So packets supposedly on the same subnet that have to
> traverse the router to get to a different LAN port will often have low
> throughput, as the CPU needs to examine and route each packet, and
> router CPUs are not normally very fast. Routers do high speed routing
> on their dedicated router hardware, and packets that need to be
> examined by the CPU will have low throughput. Low throughput = low
> bandwidth. Low bandwidth compared to the 1 gigabit/s of the LAN port
> means that if there is too much traffic, packets will be dropped to
> reduce the traffic down to the amount that can actually be routed
> between the LAN ports. This is a likely scenario for your setup - UDP
> packets traversing the router between LAN ports are too much for the
> router CPU to handle and are not being routed by the dedicated
> hardware as router hardware usually does not do bridging. So some UDP
> packets get dropped. CPU routed packets on my old ERLite router had
> only about 150-200 Mbit/s bandwidth available once I had all my
> firewall rules installed. Packets routed on its dedicated routing
> hardware had 1 gigabit/s bandwidth.
>
> The plus side of this LAN port configuration is that if you really are
> routing between the LAN ports rather than bridging (ie each LAN port
> has a different subnet on it), then you can get full gigabit routing
> between all the ports (including the CPU/router hardware port and
> access via that to the WAN port). That assumes that you only use the
> routing features that are handled on the dedicated routing hardware.
> QoS, for example, will usually require the packets to be routed via
> the CPU.
>
> The other way of organising router LAN ports has all the LAN ports on
> a separate internal hardware switch, and also on that switch is an
> internal Ethernet port to the router hardware and/or the router CPU.
> Sometimes there is a separate port for the CPU and the dedicated
> router hardware. This separate switch works exactly the same as a
> normal external Ethernet switch. It is usually moderately intelligent
> - it has VLAN capabilities. You can configure the switch VLANs so
> some of the LAN ports just connect to each other over a VLAN
> (bridged), or there can be a VLAN that connects them to the Ethernet
> port to the router, or some combination of VLANs. With this sort of
> LAN port configuration, if you have several of your LAN ports on the
> same subnet, you can just configure them to be bridged on the same
> VLAN and there will not be any bandwidth problems with the bridged
> packets. The bridged packets are handled entirely in the switch
> hardware and are never seen by the CPU or router hardware. The
> downside of this sort of LAN port configuration is that there is
> contention between the LAN ports for the CPU/router hardware port when
> packets between the LAN ports actually need to be routed instead of
> bridged. You potentially have say 4 LAN ports wanting all their
> traffic to be routed via one single gigabit port to the CPU/router
> hardware. In some routers using switched LAN ports, the WAN port can
> also be on the switch, causing contention between WAN packets and LAN
> packets for access to the CPU.
>
> Really good routers that use switched LAN ports solve the problem by
> having a higher speed on the CPU/router hardware port, so if there are
> 4 x 1 gigabit/s LAN ports, the CPU/router hardware port will be 4
> gigabits/s. Such routers are usually far beyond the means of home
> users to ever contemplate buying.
>
> So what I recommend to people buying a router is to find out which
> sort of router it is and whether that is actually the sort they want,
> depending on what they want their LAN ports to be used for. I have
> Ubiquity ER4 router, which has separate LAN ports. In the Ubiquiti
> routers, there are others (such as the ER-X) which have switched LAN
> ports, and some that have a mixture (such as one separate LAN port and
> 5 switched LAN ports). If you have a small network where you do not
> need any more LAN ports than are switched LAN ports on the router,
> then getting a router with switched LAN ports saves the need to buy a
> separate switch. But if your needs are larger than that, I think it
> is best to get a router with non-switched LAN ports and also get
> yourself a decent switch or two to go with it. Do all the routing on
> the router and all the bridging on the switches. I have a Ubiquiti
> ES-24 Lite switch to go with my ER-4. It is a full commercial grade
> switch with all the features I might ever need in a switch, except for
> POE. I also have a simple unmanaged 5 port switch to use whenever I
> have only one Ethernet connection at a location and need more - I can
> use it until I get a new cable installed to that location from my
> ES-24 main switch.
> _____


I appreciate the detailed explanation.  At present all my ports on my
home network are connected via switches and only one port on the router
has the top switch in the tree connected to it. So the problem should be
solved and certainly seems to.

I am curious about the mention of dropped UDP packets being the
problem.  I thought MythTV v30 and beyond used the TCP method of dealing
with HDHR tuners so you could get the virtual channels, etc. Maybe I
don't understand that part of it.

Jim A


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Re: HDHomeRun tuners and network switches [ In reply to ]
On Fri, 21 Jan 2022 05:23:32 -0500, you wrote:

>I appreciate the detailed explanation.? At present all my ports on my
>home network are connected via switches and only one port on the router
>has the top switch in the tree connected to it. So the problem should be
>solved and certainly seems to.
>
>I am curious about the mention of dropped UDP packets being the
>problem.? I thought MythTV v30 and beyond used the TCP method of dealing
>with HDHR tuners so you could get the virtual channels, etc. Maybe I
>don't understand that part of it.
>
>Jim A

I had not realised that MythTV now used TCP for recording from HDHRs.
Since TCP handles packet loss by retransmission of lost packets, you
would expect that it would not be bothered by an occasional lost
packet. But even TCP can be overwhelmed by too many packet losses -
it slows down the transmission rate until the packet loss goes away.
So for a TCP connection to have a bad recording, the router throughput
for the bridged packets would need to be so low that the TCP
connection speed became lower than the speed of the channel being
recorded. Which is entirely possible - routers really are very bad at
doing bridging. However, if this was happening, you should see
disconnect/reconnect messages about losing the TCP connection and
having to restart it. I would hope that sort of thing would always be
logged, as it is a fairly drastic problem that would cause loss of
quite a bit of a recording.
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Re: HDHomeRun tuners and network switches [ In reply to ]
On 1/21/22 5:23 AM, Jim Abernathy wrote:
> I am curious about the mention of dropped UDP packets being the problem.


FWIW, dropped packets at gigabit speeds was one of the motivating
factors for me retiring my prior Nvidia ION MythTV box. UDP traffic
having the more-noticeable outcome, and HDHR transforming that outcome
into something actually visible with the eyes.

All other variables identical, the replacement system with Intel gigabit
ethernet doesn't drop a packet.



-WD

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Re: HDHomeRun tuners and network switches [ In reply to ]
On 1/21/22 05:52, Stephen Worthington wrote:
> On Fri, 21 Jan 2022 05:23:32 -0500, you wrote:
>
>> I appreciate the detailed explanation.  At present all my ports on my
>> home network are connected via switches and only one port on the router
>> has the top switch in the tree connected to it. So the problem should be
>> solved and certainly seems to.
>>
>> I am curious about the mention of dropped UDP packets being the
>> problem.  I thought MythTV v30 and beyond used the TCP method of dealing
>> with HDHR tuners so you could get the virtual channels, etc. Maybe I
>> don't understand that part of it.
>>
>> Jim A
> I had not realised that MythTV now used TCP for recording from HDHRs.
> Since TCP handles packet loss by retransmission of lost packets, you
> would expect that it would not be bothered by an occasional lost
> packet. But even TCP can be overwhelmed by too many packet losses -
> it slows down the transmission rate until the packet loss goes away.
> So for a TCP connection to have a bad recording, the router throughput
> for the bridged packets would need to be so low that the TCP
> connection speed became lower than the speed of the channel being
> recorded. Which is entirely possible - routers really are very bad at
> doing bridging. However, if this was happening, you should see
> disconnect/reconnect messages about losing the TCP connection and
> having to restart it. I would hope that sort of thing would always be
> logged, as it is a fairly drastic problem that would cause loss of
> quite a bit of a recording.

I think we can say that the TP-Link Archer AX50 is not a good switch.
After having it configured with just one of it's port connected to my
tree of switches the problems have gone away.  I recorded and watched a
lot of NFL football this weekend and no issues with the HDHR tuners.
Everything I recorded on the production backend was perfect as well,
which uses the WinTV quadHD PCIe card. The test backend with the HDHR
tuners was a Rasberry Pi 4 only running the backend. I used a Nvidia
Shield TV (8.23) as the frontend.

Thanks for all the suggestion. So my new BKM (best known methods) is
never use but one of the RJ-45 ports of a consumer AP/Router

Jim A


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