[mythtv-users] Remote recorder advice

[Douglas Paul]

Hi,

On Tue, Mar 10, 2020 at 09:51:04PM +0000, Andrew Wilkinson wrote:
> Thanks, I wasn't aware of those settings. On the page
> https://www.mythtv.org/wiki/User_Manual:Setting_Up#Slave_Backend it says
> that "The design requires that all backends be powered on whenever any task
> is running. You cannot save power by having some backends powered off even
> if they are idle. Once all backends are idle they can all be powered off."
> Does this mean that all the slave backends can be powered off, or that the
> slaves and master have to be turned off together? I was hoping to keep the
> master running 24/7 so we can watch recordings quickly, but that it would
> turn the slave on and off as needed to do recordings.

I'm not sure why it would say that.

If you look here:

https://www.mythtv.org/wiki/Setup_General

Look at the option 'Master backend override'.

Basically to do what you want, you need a few things:
  * The master backend override option
  * A common directory for recordings for all backends (NFS mounted in
    the same place on each)
  * Under 'Shutdown/Wakeup Options' set the 'Startup before recording'
    option. It has to be long enough for the slave to POST, boot, and
    start the backend. I used to use 300 seconds (5 minutes)
  * The options mentioned before, and on that page under 'Backend Wakeup
    settings'
      -- It seems that documentation is misleading or wrong, unless the
      implementation changed changed I used this. The SleepCommand is run
      on the slave to shut it down -- such as '/sbin/halt -p'. The
      WakeCommand is run on the master backend to wake up the slave
      before a recording. This would be your WoL script for example.

I ran this way for years, shutting down slaves exactly for the reason 
to save power. I had two slaves, and they would only both be on if all
the recorders were needed. I have no tuners on my master backend to this
day. And, I have no problems accessing recordings when the slave is off.

The only caveat is that storage groups might not interact well with
this. So, you might not want to use them with this.

-- 
Douglas Paul