Subject: SIOCGIFBRDADDR?

From: Alan Robertson <[email-masked]>
Date: Thu, 01 Aug 2002 08:04:21 -0600

Hi,

Some folks using the linux-ha (heartbeat) software have been running into 
some network-related problems, and Alan Cox suggested that you folks could 
help us out.

One of the ways you can configure linux-ha protocols is to send broadcast 
packets.  In this case, our software needs to get the broadcast address from 
the OS, so we can proceed.  We currently use the SIOCGIFBRDADDR ioctl to do 
this for us.  This has worked pretty well for us for quite some time, but 
recently some users have run into some problems.

It appears that if one configures an interface using ifconfig, then the 
SIOCGIFBRDADDR ioctl works quite nicely to determine the broadcast address 
of an interface.

However, if one uses the iproute2 tools to configure the interface, then it 
appears that the SIOCGIFBRDADDR ioctl returns bogus results on that interface.

Is this supposed to be the case?

Is there a different method we're supposed to use instead of SIOCGIFBRDADDR?

	Thanks!

	-- Alan Robertson
	   [email-masked]
	   http://linux-ha.org/