Re: HSR: How to set IF_OPER_LOWERLAYERDOWN?

On Tue, 26 Jun 2012 22:28:51 +0000
Arvid Brodin [off-list ref] wrote:

Hi,

According to Documentation/networking/operstates.txt a network interface have an
operational state and an administrative state.

If I understand things correctly the administrative state is the desired state set by
userspace, and the operational state is the actual state which depends on things like the
administrative state, whether a carrier is present, or (for virtual interfaces lite VLAN)
whether the lower interface is available.


In the driver I'm writing (for the "HSR" redundancy protocol) a hsr (virtual) interface is
useable as long as any of its (physical) slaves are useable. I.e. the operstate of a hsr
device might be set like this:

void hsr_set_operstate()
{
	if (!is_admin_up(hsr_dev)) /* Check IFF_UP */ {
		set_operstate(hsr_dev, IF_OPER_DOWN);
		return;
	}

	if (is_operstate_up(slave1) || is_operstate_up(slave2)) /* Check IF_OPER_UP */
		set_operstate(hsr_dev, IF_OPER_UP);
	else
		set_operstate(hsr_dev, IF_OPER_LOWERLAYERDOWN);
}

According to 802.1X example in documentation to set it down you need to set IF_OPER_DORMANT
not IF_OPER_LOWERLAYERDOWN.  Probably a kernel bug in there somwhere.