[mythtv-users] Issue with back end host address

[Stephen Worthington]

On Tue, 15 Jun 2021 08:17:26 -0500, you wrote:

Ignore the BackendServerIP setting - I checked in a new MythTV install
I have in a virtual machine and it is not present there, so that value
is historical and no longer used.  The BackendServerAddr setting is
the current one.

>Deleting the value of BackendServerIP changes the issue. Now 127.0.0.1 
>is treated as the one-and-only Primary IP Address plus it is assigned to 
>a new instance of BackendServerIP:
>
>1. Stop mythbackend
>2. Launch mythtv-setup
>3. General.
>4. Host Address Backend Setup
>5. Uncheck Listen on All IP Addresses
>6. Select Primary IP Address/DNS Name
>7. The only IP listed is 127.0.0.1.

I am guessing that this is the problem.  Mythtv-setup is not seeing
all the IP addresses in use on the PC for some reason, and is only
allowing you to set an IP address that it sees as being present.  On
my backend, where I have two IPv4 addresses and two IPv6 addresses on
br0 (bridged eth0/tap0), it puts all those addresses in the drop down
list, along with 127.0.0.1 and ::1 and the IPv6 link-local addresses
and the address on my OpenVPN tun0 interface.  If you are only getting
127.0.0.1, there must be something that is preventing mythtv-setup
from seeing the Ethernet interface - it is only seeing the lo
interface.  So what does the "ifconfig" or "ip addr" command show?  Do
all the expected IP addresses show up?  Do you get different results
running those commands as user mythtv and root?

You could try manually changing the MasterServerIP and
BackendServerAddr entries directly in the database.  But if
mythbackend then can also not see the Ethernet interface, it will not
work very well.

When the "Listen on All IP Addresses" option is on, mythbackend will
ignore the IP address settings and listen on both 0.0.0.0 and :: (for
an IPv6 enabled PC), or 0.0.0.0 only (for an IPv4 only PC).  You can
see what it is listening on with this command:

netstat -anp | grep mythbackend | grep tcp

I am not sure if netstat will need to be run as root to see all the
connections - I always run it as root.  This is what I get:

root at mypvr:~# netstat -anp | grep mythbackend | grep tcp
tcp        0      0 0.0.0.0:6543            0.0.0.0:* LISTEN
3276/mythbackend
tcp        0      0 0.0.0.0:6544            0.0.0.0:* LISTEN
3276/mythbackend
tcp        0      0 0.0.0.0:6549            0.0.0.0:* LISTEN
3276/mythbackend
tcp        0      0 0.0.0.0:6554            0.0.0.0:* LISTEN
3276/mythbackend
tcp        0      0 127.0.0.1:6543          127.0.0.1:44296
ESTABLISHED 3276/mythbackend
tcp        0      0 127.0.0.1:6543          127.0.0.1:44298
ESTABLISHED 3276/mythbackend
tcp        0      0 127.0.0.1:6543          127.0.0.1:41406
ESTABLISHED 3276/mythbackend
tcp        0      0 127.0.0.1:6543          127.0.0.1:41404
ESTABLISHED 3276/mythbackend
tcp        0      0 10.0.2.4:6543           10.0.2.4:49678 ESTABLISHED
3276/mythbackend
tcp6       0      0 :::6543                 :::* LISTEN
3276/mythbackend
tcp6       0      0 :::6544                 :::* LISTEN
3276/mythbackend
tcp6       0      0 :::6549                 :::* LISTEN
3276/mythbackend
tcp6       0      0 :::6554                 :::* LISTEN
3276/mythbackend

So mythbackend has four listening TCP ports on each of 0.0.0.0 and ::,
plus some established TCP connections.

Sorry about the line wrapping - my email client does not have a way of
turning that off.

>8. Select New Entry and enter 192.168.4.7.
>9. Exit Settings / Save and Exit
>10. Redo steps 4 - 7. The Primary IP is still 127.0.0.1.