On 25 February 2015 at 04:16, Lê Hoàng Anh <atwroro@gmail.com> wrote:
But I want the kickstart to automatically choose the connected interface (ie figure out the device that is connected and selecting that device) so that the PXE installation can continue. How can I change the kickstart to avoid being hardcoded to eth0?


When talking about Ubuntu, I assume you mean the preseed for debian-installer rather than using kickstart?

I used to work with dual-homed machines having Intel NICs, and trying to get debian-installer to choose the correct (connected) interface was always problematic. The default behaviour is supposed/documented to be to choose the first NIC found with an active link. In practise, it never worked for me, right through to Ubuntu 14.04; it always gave up on auto-choosing an interface and every time presented a choice on the console. At the time there were several bugs opened on various bugtrackers about it - unfortunately none of which I can locate right now (it's a tough topic to google for).

The only thing that worked for me, was to specify a fixed interface as part of kernel parameters (you can't specify in a preseed file, because the preseed file hasn't been retrieved at the point this decision needs to be made). Related issue described at https://bugs.launchpad.net/ubuntu/+source/netcfg/+bug/855921