[mythtv-users] Slave backend storage

[Stephen Worthington]

On Wed, 21 Oct 2020 10:32:14 +0100, you wrote:

>I have a scheduling conflict coming up with no obvious way around it.
>
>My first thought was to dig out one of my old USB Hauppauge tuners and make up a new source that 
>could be used to cover the issue, but then I didn't really want to spend time tampering with the 
>Master backend and possibly upset something, all for a temporary fix.
>
>So, the next idea was an ad hoc slave backend. I have a spare box I can use - in fact it is an old 
>master backend box - but the question of what to do with the storage comes up.
>
>I would rather store the video files on the MBE. Since the video directories on the MBE are already 
>shared over NFS, that would seem the simplest solution. The alternative is local storage, but then 
>when I decommission the SBE I'd have to move the vidoes; no biggy but the MBE might get confused 
>when the SBE disappears.
>
>Are there any rules out there how this would work? Problems? Suggestions?

Just adding an ATSC or DVB USB tuner is much less work than a whole
different backend.  It is not particularly difficult if it is going to
use the same EPG as you already have.  There is no need to add it as a
different source unless it is really different from your existing
sources in some way.  You can simply make it the least preferred tuner
for an existing source, by giving it a lower priority and also
specifying it as the last tuner in the scheduling order and live TV
order.  If you do that right, then it will only be used for the
recordings that currently cause conflicts.

USB tuners can be a bit temperamental, but I have found it is usually
a problem with the cable.  So when setting up a USB tuner, take great
care with the USB cable.  Some cables fit loosely into the USB sockets
and cause intermittent failures, especially if the cables get
disturbed or if the PC is in a place where it gets significant
temperature changes.  So choose a cable with a slightly larger plug
where possible, so that when you wiggle it in the socket, it does not
move much.  And make sure that the USB tuner itself and the aerial
cable it is plugged into are not easily disturbed (cat, vacuuming,
...).  A good way to do this is to lay the tuner down on a flat
surface and tape down the cables on either side of the tuner with
parcel tape.  This usually requires a slightly longer USB cable
though.  And if it is a USB 2.0 device, it is best to use a USB 2.0
socket, if you have one.  There have been complications in the past
with some USB 2.0 devices when used in USB 3.0 sockets due to driver
problems.  If the USB socket has not been used for a while, it pays to
check for lint or dust in the socket - a squirt of static-free air or
gas from your trusty PC cleaning can is recommended.  And if you are
feeling really paranoid, use contact cleaner.