"ip directed-broadcast" in VxLAN

1. What's the feature of "ip directed-broadcast" for?

• One application is Wake-on-Lan(WOL). A host device like PC can be powered on/resumed remotely. 
• Need hw/BIOS support. When host receives a WOL magic packet, it turns on. 
• Enable it in OS, linux - "sudo ethtool -s eth0 wol g"
• So server (20.1.1.1) sends a bcast packet destined to remote subnet like 10.1.1.255 to 10.1.1.0/24 network. 
• With this feature enabled under SVI, this bcast pkt will be fwded to remote subnet like a ucast pkt. 
• By default is disabled, because of the security concern. 
• This is a legacy feature starting from 2011/12?

2. Configuration and details
interface vlan 2001
  ip directed-broadcast

Says the topology with Vxlan is like

vlan 1001
10.1.1.1/24 [host2]-----+
                        |
vlan 2001               |
20.1.1.1/24 [host1]---[l2vtep]---[l2vtep]---[gw of svi1001/2001]

* host1 sends pkts dstIp=10.1.1.255
* pkts follows vxlan to reach gw
* gw routes pkts back l2vtep as a ucast pkt

3. Caveats

• Arista EOS has a bug - 217001, when the vlan is included vxlan interface, the directed-bcast traffic will be shaped by PDP. 

yr252.23:14:18#sh pl trident l3 software host-table | beg 10.50.51.255

   Entry: 0, HwEntry: 0x6002a50, Type: v4Uc, Vrf:  0, Host: 10.50.51.255/32

Bucket: 687, state: 0x00011