[mythtv-users] Upgrade Madness

Stephen Worthington stephen_agent at jsw.gen.nz
Sat Dec 4 12:16:19 UTC 2021

On Fri, 3 Dec 2021 20:46:46 -0600, you wrote:

>I have an existing BE/FE combo machine that is dying.  It is running 
>Ubuntu 16 and MythTV v30.
>I have a new box that I installed Xubuntu 20 LTS on.  But I then 
>discovered that the ppa MythTV requires v31 on focal.
>So my question is how to best proceed.  I don't know where in the 
>install/upgrade process MythTV upgrades the database schema.  Can I 
>install MythTV v31, restore the v30 database, and get MythTV to update 
>that database schema?

Yes.  On running mythtv-setup or mythbackend, if the database schema
is out of date, the database will be backed up and then the schema
will be upgraded.  So the preferred way of moving an older database
onto a machine with a newer MythTV install is to get the new machine
running correctly with a newly create database, then shut down
mythbackend and restore the database from the old machine.  Then run
mythtv-setup.  If you run mythtv-setup from the command line, you will
see it telling you what it is doing as it backs up the existing
database and then upgrades the schema.  This does take a while, but
eventually it will be done and the mythtv-setup GUI will be displayed.

>To further confuse things, I have setup the new json sql-lite schedule 
>grabber but not enabled it.  So I'm still using the old method.  Should 
>I try to implement that on the dying machine first, so that 
>configuration can carry over to v31 which as I understand requires the 
>new grabber.

I would suggest setting up the new grabber on the new PC and getting
it working there, before moving the old database onto the new PC. Then
adjust any settings in the updated version of the old database to
those needed for the new grabber.

>Also, I have to have a working Lirc so I can transmit IR signals to the 
>TV and STB.  Could I demote the current backend to be a slave backend 
>while I get things working?  Or at least point the old machine to the 
>new one's database?

You can not mix versions of MythTV, so the old and new machines can
not use the same database, unless you upgrade the old one, which seems
to be something you are trying to avoid.

Getting lirc working on the new machine depends on how your IR remote
works - if you have IR hardware in the new PC, you can just get that
going before moving the database onto the new PC.  But if you need to
move the old IR hardware to the new PC and it needs to be used on the
old PC too (it is on a tuner, for example), then you may have to do
that when you have a large enough gap in your recordings on the old PC
so that you can get it working and then move the IR receiver hardware
back to the old PC before the next recording.

>Does anyone have a working MCE USB receiver/transmitter Lirc 
>configuration?  I have just started looking at the new version of Lirc.  
>Thankfully I know about the script to fix Ubuntu's botch of the Lirc 

I have an MCE remote and two Hauppauge remotes working with 20.04
using the devinput kernel driver.  The upgrade procedure is around in
posts on this list.  But you need to use the IR transmitter to control
an STB.  Getting an IR transmitter working in the new lirc requires
that you set up lirc using the old method of a separate mceusb driver,
rather than the kernel devinput driver which is a receiver only.  I
have never done that, and the documentation of how is poor to
non-existent.  I believe the configuration you need to use is to
select the "default" driver instead of the "devinput" driver, and to
use the mceusb.lircd.conf file in /etc/lirc/lircd.conf.d/ directory
instead of devinput.lircd.conf.

See this page:


and search for "mce".

There are a few examples of using lirc with transmitters:


but they are very specific to the hardware being used.  They do give
some good clues though.

Given the likely difficulties in getting this going, I think it will
be necessary to spend some time on it, and it will have to be done on
the new machine.  This would obviously work best if you have separate
IR hardware in both PCs.  I think you need to get lirc working before
you do anything else, as it is critical to your setup.  It can be done
without doing any MythTV setup on the new PC, and I think it would be
best to be done before anything else.

I can backup my lirc settings on my MCE box and try it out - I have a
full keyboard on that PC so I can run without an IR remote without
undue hardship.  And the current author of lirc (Alec Leamas) has been
on this list recently, so he may be available to help too.

This is what lsusb shows for my MCE IR hardware:

Bus 005 Device 002: ID 0609:031d SMK Manufacturing, Inc. eHome
Infrared Receiver

It is fairly generic.  What hardware are you using?

>Suggestions appreciated.

More information about the mythtv-users mailing list