Wake-On-Lan fail with VM

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How Wake-On-Lan Work

  • Cloud server will request "Agent1" to wake up another "Agent2"
  • Agent1 will send broadcast magic packet which payload is the MAC address of Agent2.
  • When Agent2 receive magic packet, it power on device.

RTENOTITLE

Routing Table Problem with VM installed

  • There are two broadcast address.
    • Global broadcast address: 255.255.255.255
    • Local broadcast address: ex: 172.22.15.255
    • RTENOTITLE
    • PowerOnOff plugin send WOL packet to global broadcast address.
  • We found VM network adapter will modify global broadcast route rule that may makes broadcast fail.
    • Wol-route-1.png
  • Routing priority of windows:
    1. Small metric rule will pick up first.
    2. Then it will pick up the first interface that avaliable.
  • PowerOnOff plugin will choose "255.255.255.255 | 192.168.189.1" rule from routing table in this example.

Possible Solution

  • Send WOL packet with local broadcast address to each interface in current agent.