Requirement:
Some Customers may still want to allow unknown unicast traffic with BC/MC optimization enabled in Layer 3 VLAN.
Solution:Starting AOS version 6.5.4.8 and later, a new knob has been introduced in "interface vlan", bcmc-optimization allow-unknown-unicast. When this is enabled, Controller forwards all unknown unicast packets, rather dropping it.
Prior to AOS 6.5.4.8, such unknown unicast traffics were dropped by the Controller along with broadcast and multicast traffic when BC/MC optimization is enabled in Layer 3 VLAN with below exceptions,
1. NS/ARP- controller will do proxy-arp/proxy-nd or flood
2. DHCP/DHCPv6- Flooded
3. VRRP- Flooded
4. NA/RS/RA- Flooded
5.ADP
Configuration:(Aruba7240-164.10) (config)#interface vlan 2
(Aruba7240-164.10) (config-subif)#bcmc-optimization allow-unknown-unicast?
allow-unknown-unicast Do not drop flooded unicast traffic
<cr>
Verification
(Aruba7240-164.10) #show interface vlan 2
VLAN2 is up line protocol is up
Hardware is CPU Interface, Interface address is 00:1A:1E:03:D1:C8 (bia 00:1A:1E:03:D1:C8)
Description: 802.1Q VLAN
Internet address is 2.2.2.2 255.255.255.0
IPv6 Router Advertisements are disabled
Routing interface is enable, Forwarding mode is enable
Directed broadcast is disabled, BCMC Optimization disabled ProxyARP disabled Suppress ARP enable
BCMC Optimization Allow Unknown Unicast: Enabled
Encapsulation 802, loopback not set
MTU 1500 bytes
IP NAT Inside is enabled on this interface
Last clearing of "show interface" counters 0 day 1 hr 10 min 48 sec
link status last changed 0 day 1 hr 8 min 38 sec
Proxy Arp is disabled for the Interface