[mythtvnz] hdhomerun doesn't connect on restart when connected directly to the lan port

[Stephen Worthington]

On Sat, 27 Apr 2013 14:37:28 +1200, you wrote:

>On Sat, Apr 27, 2013 at 1:39 PM, Paulgir <paulgir at gmail.com> wrote:
>
>> Apr 27 13:13:42 myth dhcpd: No subnet declaration for eth0 (no IPv4
>> addresses).
>> Apr 27 13:13:42 myth dhcpd: ** Ignoring requests on eth0.  If this is not
>> what
>> Apr 27 13:13:42 myth dhcpd:    you want, please write a subnet declaration
>> Apr 27 13:13:42 myth dhcpd:    in your dhcpd.conf file for the network
>> segment
>> Apr 27 13:13:42 myth dhcpd:    to which interface eth0 is attached. **
>> Apr 27 13:13:42 myth dhcpd:
>> Apr 27 13:13:42 myth dhcpd:
>> Apr 27 13:13:42 myth dhcpd: Not configured to listen on any interfaces!
>>
>
>Clearly you have misconfigured DHCP. It's probably working after 20 seconds
>because it's defaulting back to link-local addresses.
>
>I know nothing about that DHCP server, but I think this looks wrong:
>
>> host myth-eth0 {
>>  hardware ethernet 14:da:e9:dc:51:a1;
>>  fixed-address 10.99.0.1;
>>  }
>>
>
>DHCP servers listen on a network interface - it can't function until the
>interface has an IP address. So obviously you can't use a DHCP server to
>assign an IP address to the interface that the DHCP server is supposed to
>be listening on. But that's what this configuration seems to be trying to
>do. You should assign 10.99.0.1 to eth0 in the normal way (whatever that is
>for ubuntu) and leave this section out.
>
> subnet 10.99.0.0 netmask 255.255.255.0 {
>>  range 10.99.0.50 10.99.0.250;
>>  option subnet-mask 255.255.255.0;
>>  option broadcast-address 10.99.0.255;
>>  option routers 192.168.2.2;
>>  }
>>
>
>I can't imagine you need the "option subnet-mask" line in there - you
>already supplied the netmask.
>I assume "option routers" is setting the gateway on the client interface.
>But the client is not going to be able to connect to 192.168.2.2 - it's not
>on the same subnet and there is no router or anything to help. This should
>be set to the address of the myth box on that subnet, i.e. 10.99.0.1. If
>the hdhr needs connectivity to the rest of the network then you'll need to
>do some iptables config on the myth box.
>
>Cheers,
>Steve

Steve is right, I have just been testing the config on my laptop.  I
connected it via WiFi and put its eth0 onto my spare 100 Mb/s ethernet
switch so it thinks there is an ethernet connection and tried out the
config. The dhcpd server can not assign the address to the eth0 port
and then serve addresses to the same port - the eth0 port has to be
manually configured before the dhcpd server starts.

Disconnect the ethernet cable from the MythTV box.  Edit
/etc/dhcp/dhcpd.conf.  Delete the entire "host" declaration.  Delete
the "option subnet-mask" line from the subnet declaration.  Change the
"option routers" setting to 10.99.0.1.  Save the file.  Then go to the
Network Manager widget, right mouse button, Edit connections, Wired
and edit the setup for the eth0 port (by default it will be called
"Wired connection 1".  Set up the eth0 port with a manual IPV4 IP
address of 10.99.0.1, netmask 255.255.255.0.  Set the gateway address
to the address of the WiFi port shown by ifconfig.  Leave the DNS
servers and Search domain settings empty.  Save the config.  Connect
the ethernet cable to eth0.

Run the command:

  start isc-dhcp-server

Run ifconfig and it should show 10.99.0.1 for the IPv4 address. And
"ps -e | grep dhcp" should show that dhcpd is running.  Plug in the
HDHomerun and see if it works - I think by default dhcpd will log a
message in syslog about it getting a lease, but I can not test that
here as I do not have a spare device to connect to that ethernet that
needs an address via DHCP.