[mythtv-users] Fedora, ceton, systemd, and mythbackend

[Hika van den Hoven]

Hoi Justin,

Monday, January 26, 2015, 12:32:06 AM, you wrote:

> I seem to run into a fun interplay between Fedora, my Ceton InfiniTV card,
> systemd, and my mythbackend (which handle two remote frontends).

> 1. The system boots.
> 2. The ceton driver loads, and for some reason systemd promptly renames
> this to network interface p5p1.
> 3. In the meantime, my actual ethernet interface (p5p2) is busy waiting on
> a response from my DHCP server.
> 4. Systemd loads mythbackend, which currently depends on
> network-online.target.
> 5. Because network interface p5p1 is up and running and has an IP address
> then YAY, as far as system is concerned the network is online. Mythbackend
> is a go to start.
> 6. Mythbackend starts, but doesn't actually listen on the not-yet-available
> ethernet connection to the outside world (p5p2).
> 7. At some point in the future, the DHCP server gets back to the backend
> and gives it a configuration for p5p2, meaning it can talk to the outside
> world. However it's too late for mythbackend to listen on this interface,
> and is not reachable from any of the remote frontends.

> This happens predictably and repeatably. I have no idea why systemd feels
> compelled to rename ctn0 to p5p1, or how to convince network manager that
> even though p5p1 looks and feels like a connection to the outside world,
> it's not. I already have mythbackend.service configured as starting
> "After=network-online.service" but clearly that's not enough.

> Google searches for "systemd network interface naming" and umpteen
> varieties of that only gives results talking about the wonderful new
> feature of systemd that will bring predictable network interface naming to
> Linux.

> First off, has anyone else seen this behavior?

> Secondly, does anyone have any suggestions on the right approach? Should I
> tweak systemd to not rename the interface? Should I try and get network
> manager to understand that p5p1 (or ctn0) is not actually a useful network
> interface? Should I just kludge it and put "sleep 10" before the
> mythbackend starts?

> Thanks,
> -jdm

A  temporary  workaround could be to put all processes needing network
on  a  2? second wait-loop before starting up. Hopefully that would let
them  get  the  right interface. Am I correct that systemd doesn't use
udev, but its own variant? Because that's where I would look.
Furthermore,  I  keep  far  from  systemd for it's to inaccessible for
troubleshooting  and  I have heard and experienced to many things like
you name. I guess it needs another 5 years to mature.

Tot mails,
  Hika                            mailto:hikavdh at gmail.com

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Zonder leven is er geen hoop
Het eeuwige dilemma
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