Re: unresponsive vlan on top of bond with fail_over_mac=active

On Wed, Oct 10, 2012 at 08:34:31PM -0700, Jay Vosburgh wrote:

Michal Kubecek [off-list ref] wrote:
	What network device are they using that requires fail_over_mac
to be set to active?

I would have to ask for exact configuration, all I know for sure is that
the problem was reported for s390x (S390-64) architecture. I reproduced
it with VMware Workstation virtual devices which emulate Intel e1000.

	I tested some of this out earlier this year, and I don't recall
having problems (although I'm not sure I did this exact test).  The
dev_uc_add() logic (in __dev_set_rx_mode) would put the underlying
device into promiscuous mode if the hardware didn't support multiple
unicast MAC addresses. dev_uc_add() was invoked by vlan_sync_address(),
which is called by the vlan NETDEV_CHANGEADDR notifier callback.

Yes, this part works fine, I checked uc list with live crash session.
But as bonding driver doesn't set its ndo_set_rx_mode method, the
iformation about second MAC address doesn't propagate down to the
slaves.

	Bonding does propagate promisc to its slaves, but (as you point
out) not the uc lists; is the hardware in question something that
supports multiple unicast addresses (IFF_UNICAST_FLT)?  The device I
tested with does not support IFF_UNICAST_FLT, and (as I recall) would
end up in promisc mode.

My tests were done with (emulated) e1000 which supports unicast
filtering (up to 14 addresses, according to what I've seen in the
driver). I'm not sure about the devices on s390x.

                                                      Michal Kubecek