# Knowledge Base - WoL does not boot all the machines

## 1. [Wake on LAN](https://www.manageengine.com/products/oputils/wake-on-lan.html?wol-kb) tool does not boot all the machines.

Check the following:

### On the Machine

1. NIC should be wake on LAN complaint  
2. In BIOS WOL should be enabled  
3. Most external NIC's will have 3 PIN WOL cable which has to be connected to the motherboard.  
4. You can see a blinking light in the NIC even if the machine is powered off.  
5. Ensure that the power supply to the machine is switched ON.

### On the Network

For [Wake On LAN tool](https://www.manageengine.com/products/oputils/wake-on-lan.html?wol-kb) to work across subnets (or VLANs):

1. Enable IP Directed broadcasts on the routers/gateways. This ensures that the WOL packets are not blocked.  
2. IP directed broadcasts has to be enabled in all the required routers/gateways/switches along the path. This depends on the network design.  
3. Alternatively, you can also add an access list in the switches to allow UDP packets from a specific machine to other subnets. For example:  
   **Access-list 101 permit udp 192.168.110.103 host 192.168.116.255 eq 5000**, where  

   - `192.168.110.103` refers to the machine generating the WOL packets  
   - `192.168.116.255` refers to broadcast address that is being permitted  
   - `5000` refers to the port from which the WOL packet is being sent from the generating machine  

   This again needs to be enabled in all the routers/switches along the path.

[Questions](https://www.manageengine.com/products/oputils/knowledge-base.html#wake-on-lan)

Know more about OpUtils' [Wake on LAN](https://www.manageengine.com/products/oputils/wake-on-lan.html) software in the feature pages.