Controls if a new network namespace should inherit all current settings under /proc/sys/net/{ipv4,ipv6}/conf/{all,default}/. By default, we keep the current behavior: for IPv4 we inherit all current settings from init_net and for IPv6 we reset all settings to default.
If set to 1, both IPv4 and IPv6 settings are forced to inherit from current ones in init_net. If set to 2, both IPv4 and IPv6 settings are forced to reset to their default values. If set to 3, both IPv4 and IPv6 settings are forced to inherit from current ones in the netns where this new netns has been created.
Default : 0 (for compatibility reasons)