Network Settings in the OS X part lost after parallel installation of mate

I made a carbon copy (i.e. a clone) of the existing OS X 10.5.8 installation on my PPC to a second harddisk. Booting the box with the clone went well. After that I reduced the size of the OS X partition, removed the original harddisk and changed the new harddisk from slot B to slot A. Again no problem with booting OS X. Then I made a parallel installation of Ubuntu Mate 16.04.1 PPC. Everything works perfectly, both operating systems boot well. With the only exception that when booting OS X there is no network connection, but at the same time it says “connected” in system settings. The IP-adress shown seems to be the “external” IP-adress, i.e. the numbers are not 192.168.x.xxx aus usual. Tried to use the settings of the parallel Ubuntu-installation, but that does not work as well.

Does anyone has an idea what happened and what to do?
Does it make sense to boot the G5 with the original OS X harddisk reinstalled, read out the network settings used there; reinstall the new harddisk (with the parallel installation …) and use the original network settings of the prior OS X installation?