On 03/14/2018 12:27 PM, Per Jessen wrote:
That is nonetheless how you code it to listen on _any_ address (INADDR_ANY). That is also how it is displayed when you look at open sockets with 'netstat' or 'ss'. When I write '0.0.0.0', I usually also imply '::', although that isn't quite correct.
Does the DHCP server actually listen on any address? Or only it's own and broadcast addresses? The 0.0.0.0 or :: in IPv6 means unknown, while waiting for an address to be assigned. A DHCP client will do the discovery and initial request to the broadcast address and then to the server's address. At what point does it ever use any other? Why would the server listen on any other? 0.0.0.0 is used as the default route within an OS, but then the packet get sent to the appropriate route. But that 0.0.0.0 will never be seen on the wire. On the other hand, a DHCP discovery packet, will show 0.0.0.0 as source and 255.255.255.255 as destination, on the wire. BTW, I tried that experiment. I turned off my DHCP server and plugged in my notebook computer. It sent DHCP discover packets several times over about 3 minutes, but then stopped and sent another 5 minutes later. As I had turned my DHCP server on again, I don't know what would have happened after that. This was with 42.3 & Network Manager. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org