Can dhcpclient handle broadcasting ?

Chaigneau, Nicolas nicolas.chaigneau at
Wed Jul 9 10:38:56 CEST 2014

OK, the answer is no. It fails because:

"If the socket protocol supports broadcast and the specified address is a broadcast address for the socket protocol, sendmsg() will fail if the SO_BROADCAST option is not set for the socket."

The socket set up by dhcpclient.c needs something like this :

int so_broadcast = 1;
status = setsockopt(sockfd,
    &so_broadcast, sizeof so_broadcast);

De : at [ at] De la part de Chaigneau, Nicolas
Envoyé : mercredi 9 juillet 2014 09:54
À : freeradius-users at
Objet : Can dhcpclient handle broadcasting ?


I'm trying to use dhcpclient to test broadcasting of a DHCP Discover.

I am root so I can use source port 68.
I'm sending the packet to the broadcast address.

I get the following error (returned by sendmsg, called from "sendfromto"): "Permission denied".

Is it possible to use dhcpclient from FreeRADIUS in broadcast mode ?

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