Wake-On-Lan to other subnet

Mac addresses in other IP subnets cannot be reached directly. For this reason, the broadcast address of the remote network must be included when calling the wake-up command. If a computer with the Mac address 0A-00-27-A0-0E-14 is to be woken up from the network 10.8.0.0 with the subnet mask 255.255.0.0 (Class B), the wake-up command is as follows

wol.exe 0A-00-27-A3-0E-18 10.8.255.255

Run this command with the command line tool wol.exe, which is included with the WakeOnLanTool and the Ping Tool. If you don't really need these tools, you can simply download them and use only the wol.exe command line tool. The tools do not require installation. If you have a Class C subnet mask, the broadcast address would be 10.8.0.255.

However, this alone is not enough. The network must be configured for this, since the router does not forward the Magic Packet by default.

Example configuration Cisco router / HPE Aruba router

To transport the Magic Packet across router boundaries, the routers must be configured correctly for this. For Cisco routers, for example, this can be achieved with the ip-directed broadcast command on the LAN interface in the target LAN, i.e. the subnet in which computers are to be woken up. This also works for HPE Aruba routers. In order not to let all broadcasts pass through for security reasons, an access list should be configured in which the machines authorized to send are limited. If, for example, only a specific server - in this case the Wake-On-Lan server with the IP address 10.2.1.1 - is to be authorized for network-wide broadcasts, the following configuration is used:

Router(config-if)#ip directed-broadcast 101
Router(config)#access-list 101 permit udp host 10.2.1.1 any

Check the functionality

To see if a Wake-On-Lan packet has crossed the router boundary, you can look at the "matches" within the access-list using show access-lists:

Router#show access-lists
Extended IP access list 101
10 permit udp host 10.2.1.1 any (12 matches)

If the number of matches increases when the wake-up command is sent, it is certain that the Magic Packet has overcome the router. Alternatively, a Wireshark measurement on the PC helps - have a look at UDP broadcasts. If the packet can be recorded here, but the PC shows no movement, this is a sure indication that the problem is not caused by the network. There are several settings on the PC to enable Wake-On-Lan - both on the PC itself and in the operating system. Read also the article Wake-On-Lan Windows 11, which describes the configuration of Wake-On-Lan in 8 steps. 

PingTool - a free Wake-On-Lan tool with ping (ICMP) and TCP port check

PingTool is a free ping tool for administrators. It permanently displays in a graphical interface (GUI) whether devices are responding to ping or certain TCP ports. PingTool can also be used to wake up PCs via Wake-On-Lan and perform network speed tests.

The PingTool features at a glance:

■  Permanent display of availability of ping (ICMP)

■  Permanent display of the accessibility of TCP ports (TCP ping)

■  Wake-up computers via Wake-on-Lan (Magic Packet)

■  Integrated Network-Speedtest LAN tool (manual or scheduled)

■  Mail notification in the event of failure (or other custom action)

■  Ping with timestamp to logfile

■  Dashboard for a good overview in difficult environments

■  Adjustable ping interval from 1 second to 2 minutes

■  Portable tool and free of charge, also for professional use

■  Saveable configurations (list of pinged objects)

Content

WakeOnLanTool allows you to remotely turn on computers in your network. It is ideal for standard users in a corporate network. PingTool is a software program for administrators that can wake up PCs in addition to performing ping and TCP port checks. To turn on PCs in other subnets, you need the broadcast address of the remote network.

PingTool has been developed and is optimized for Windows 11 ---> change to Ping Tool Homepage

>> back to main page Wake-On-Lan Tool Windows 11

Software: WakeOnLanTool
Categorie: Wake On Lan other subnet, Wake On Lan other network, WOL other subnet
Problem: Wake On Lan not working other subnet, Cisco and HPE Aruba routers example, Wake on LAN across subnet boundaries