Comment 2 for bug 1541544

Hello,

Ideally we would use heuristics. For example, does the hardware and the kernel know about layer2 already and e.g. does one need to change /sys/devices/qeth/0.0.0600/layer2 at all? Ideally layer2 would be set to the correct value by the kernel, and we simply lower the priority of this question, and thus stop asking users about it by default. I'm now digging into the kernel code and it looks like qeth_core_main loads layer2 by default (unless I'm missing something, I'm not a kernel developer).

I'm happy to adjust statement to a more technically correct one.
"""
Use this device in layer2 mode?
The qeth network driver is used for OSA-Express cards, HiperSockets and similar devices. Using the card in layer2 mode will make it keep the MAC addresses of IPv4 packets. Alternative is to use layer3 mode, in that mode LLC headers are removed from incoming IPv4 packets. Incorrect mode will lead to lack of connectivity.
"""
Comments on the above?

On the desktop installer, we check the connectivity by retrieving and validating check-sum of http://start.ubuntu.com/connectivity-check and thus really validate that one can access things (but i guess most mainframes are fire-walled to prevent such access). I guess in d-i context it's about being able to access the network mirror to continue installation. Not sure how we can validate automatically, given that local mirror information may not be available yet.

Lastly, I've changed the default based on the statistically insignificant survey of three people ("most mainframes use layer2, something like 60-80% probably). And a personal feeling that a bunch of things require layer2 network. The fact that our mainframe is configured with layer2 network cards was a factor too =) to ease things for us. Defaults should be sensible, or what we want the future be like.

1) ideally kernel and/or with udev assistance would do the autodiscovery of the required mode, if possible.
2) does the proposed new wording sound better to you? or how would you like the question to be worded?
3) should I keep layer2 as default?

Regards,

Dimitri.