[mythtv-users] Udev

[Stephen Worthington]

On Tue, 27 Nov 2018 06:35:50 -0500, you wrote:

>Due to recent hardware problems I've ordered a new motherboard, and because
>it has more PCI slots I've ordered more tuners. Since I now have only one
>source for recording Udev rules wont be necessary because it wont matter
>which tuner is asked to record, or will it?
>
>I may just create them anyway, but it wont be without challenge, because
>one card is the same model as an existing card.    Daryl

It is always best to know which tuner a recording was done on, as you
need to be able to work out which one may be causing a problem.  So it
is best to use udev rules to lock down the tuner arrangement, if that
is possible.  When you have multiple tuners of the same type, if you
are lucky they may have individual serial numbers that you can use in
udev rules.  But it usually does not matter, as the kernel has a fixed
order for how it enumerates the PCIe and PCI slots.  So as long as you
do not move the cards, they will always be in the same order.  You
will likely not be moving the cards around in the slots for years,
unlike with USB tuners that tend to get unplugged for some reason or
other and then you forget which USB socket they were in.  Or you plug
in another tuner and it happens to be plugged into a socket that gets
enumerated earlier than an existing tuner and moves the existing tuner
to a different tuner number in /dev/dvb.