I understand your problem. The main thing is that the ping.conf is especially used to store network parameters, so it would be problematic to try and get it from the network. On another hand, the idea to use dhcp/tftp is not bad. The very behaviour of PXE could be reproduced, depending the MAC address, for example. Beside that, if we added a parameter telling which image to deploy, then we could finally obtain a dynamical ping.conf depending only on the MAC address, thus permitting a central administration.
Before scheduling any coding, did I understand correctly your need?
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