[mythtv-users] MythTV - Video Distribution Solution?

[Dewey Smolka]

On Jan 14, 2008 1:07 PM, MythTV <mythtv at hermon.net> wrote:
> Hi everyone!
>
> I am writing from the Hermon School Dept. and we are very interested in
> the possibility of using MythTV in our district.
>
[...]
> Our goal is to have a way for teachers to access recordings in their
> classroom through a "frontend" device, that would in turn connect to a
> central server with the video storage. It sounds like MythTV would support
> this. Also, teachers would need to be able to access cable and Satellite
> through the frontend.
>
> I do realize that a cheap server wouldn't work for this environment, and
> would be willing to purchase a high-end server to handle the capacity of
> the High School. (There would be a server in each building).
>
> My question is, how many frontend devices can a MythTV server support
> concurrently? At the high school, there would be about 45 classrooms with
> front end units. (Realistically, they all wouldn't be using them at the
> same time.)

There's no limit other than the hardware itself, but the things to
keep an eye out for are disk i/o and network traffic. Still, I would
think that with server-class hardware you'd have no problem with 20 or
so frontends connected, maybe more. Others on this list know more
about this than I.

>
> What would you say the specs of a server would need to be to support at
> least 10 frontends at the same time? The front end devices and the server
> would be on their own segment of a 1-Gig backbone network so bandwidth
> shouldn't be an issue.
>
> We do understand that only one teacher would be able to change the channel
> for live TV at a time (or satellite).

Not necessarily. You can have a live TV stream (or a recorded stream)
for every tuner device installed. If you have only one tuner, then
yes, only one frontend can control Live TV. But if you have say three
tuners than three frontends can have live TV independently.

>  Can multiple people at least see, but not control, cable through
> the Front End utility?

Yes. Live TV is a recording that begins playback immediately. It's
possible for any frontend to playback the 'live' recording from the
time the recording started. It's generally a better idea to explicitly
record the program rather than capturing it through 'live TV', mainly
because 'live' recordings generally auto-expire very quickly, and
frontends (IIRC) have to be configured to display these recordings in
the Recorded Programs list. Myth will let you start watching any
recording (scheduled or live) as soon as the recording begins.

> Last, but not least, I see that MythTv supports adding multiple recording
> servers. Can we add a second recording server (or server with different
> sources) and integrate it with the overall program guide that the frontend
> use, or would the frontend machines have to be changed to point to a
> second server to see the programming available on it?

The architecture is wide open. Beyond whatever hardware (or budget)
limitations, you can have as many 'backend' machines as you like -- a
backend generally meaning a machine with a capture device. All the
backends in the system will share the same MySQL database, which is
controlled by (and usually though not necessarily hosted on the Master
Backend). All the frontends that connect through this backend will see
the same list of recordings.

> I ask because we also have DVD players we want to add as a source (a
> single channel in the program guide) and to be available to staff. (We
> realize that remote control of the DVD players isn't possible this way.)

Not sure about this, and I realize that unfortunately shifting the
content from optical disks to one of your servers is probably not an
option. I'm sure others here have some ideas.

It sounds like a great project and one that the folks on the list
would be eager to help out with. Best of luck, and make sure you keep
us posted as the project unfolds.