Accept packets with source address 0.b.c.d destined not to this host as local ones. It is supposed, that BOOTP relay daemon will catch and forward such packets. conf/all/bootp_relay must also be set to TRUE to enable BOOTP relay for the interface default FALSE Not Implemented Yet.
Nb: per interface setting (where “interface” is the name of your network interface); “all” is a special interface: changes the settings for all interfaces.
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