[mythtvnz] New install setup - recording problem

[Stephen Worthington]

On Fri, 12 Aug 2016 14:25:25 +1200, you wrote:

>>Modifying Systemd_mythbackend_Configuration looks daunting.
>
>I am sure we can work it out - I will fire up my 16.04 test box and
>see how it works.

I have done some experimenting on my test box now, and I have some
config files that should work to make systemd wait for the HVR-2200
tuners before starting mythbackend.

First, you need to tie down the tuner numbers so that the HVR-2200
tuners are always /dev/dvb/adapter0 and /dev/dvb/adapter1.  Create
this file (the name does not matter, but the .conf does):

/etc/modprobe.d/options-dvb.conf

and put these two lines in it:

#Set adapter numbers for Hauppauge HVR-2200 dual tuner (DVB-T tuners
only).
options saa7164 adapter_nr=0,1

Then add the new systemd "drop-in" override file.  First create a new
directory:

sudo mkdir /etc/systemd/system/mythtv-backend.service.d

Then in that directory, create a new file mythtv-backend-override.conf
(again, the name does not matter but the .conf does).  In that file,
put the following five lines:

[Unit]
Wants=dev-dvb-adapter0-frontend0.device
Wants=dev-dvb-adapter1-frontend0.device
After=dev-dvb-adapter0-frontend0.device
After=dev-dvb-adapter1-frontend0.device

That causes systemd to wait until /dev/dvb/adapter0/frontend0 and
/dev/dvb/adapter1/frontend0 both exist before starting mythbackend. If
either device does not exist, systemd will eventually timeout waiting
for the devices to appear and then start mythbackend anyway, but the
timeout is quite long.  I am just guessing, but it seemed like about
60 seconds.