DHCP issues with unicast

[mcb30]

(2016-06-01 13:26)simon Wrote:  At some point I was desperate enough to hack up ipxe so much that its dhcp discover looks exactly like the one ubuntu sends, but still no luck. We did realize however that the problem only occurs on some network ports, while on others it works, even if they both lead to the same switch, with both ports configured on the same vlan.
And best of all, today I could not reproduce the problem at all anymore, so I asked if they changed anything or have an idea what happened, but they don't.

This sounds like a bug in the network infrastructure. When the problem can be reproduced, how far does the DHCP response packet get before it gets dropped? (Does it get dropped, or does it just get sent to the wrong egress switch port?)

I don't really want to add a mainline patch to work around what currently looks most likely to be a configuration problem specific to your infrastructure, unless the root cause is understood and it can be shown to be something that is likely to affect other people as well.

Michael