Wake-on-LAN

Wake-on-LAN allows Lanview to send a network wake request to a device.

It is used to try to power on or wake devices that support Wake-on-LAN at firmware, network adapter and Windows driver level.

A wake request does not guarantee the device will power on. Wake-on-LAN can be frustrating to configure because there are many places where it can be blocked by firmware, drivers, switching, routing or subnet design.

If Wake-on-LAN is not working in Lanview, a useful test is to use a known Wake-on-LAN testing tool on the same network. This helps separate Lanview configuration issues from device or network configuration issues.

How Wake-on-LAN works

Lanview Server sends Wake-on-LAN packets using the configured Wake-on-LAN settings.

The target device must support Wake-on-LAN and the network must allow the packet to reach the device or subnet.

Because the target computer may be powered off, Lanview Client is not involved until the device starts and reconnects to Lanview Server.

Device and group wake

Wake-on-LAN can be requested for:

• a single device
• a group of devices
• a media access control (MAC) address where supported by console command

Group wake can be useful before maintenance windows or wider update work.

Server settings

Lanview Server has Wake-on-LAN settings for:

• broadcast address
• port
• follow up seconds
• send mode
• source address
• send attempts
• attempt delay
• whether to also send to the configured broadcast address

Default values include broadcast address 255.255.255.255, port 9 and a follow up period of 300 seconds.

The default send mode is AllEligibleInterfaces. In this mode, Lanview Server sends Wake-on-LAN packets through eligible local IPv4 LAN interfaces using subnet broadcast addresses.

Network design may require a specific broadcast address, source address, port or send mode.

Permissions

Wake-on-LAN permissions include:

Assign group wake permission carefully because it can affect many devices.

Audit behaviour

Lanview audits Wake-on-LAN requests.

The audit record shows that Lanview sent or attempted the wake request. It is not proof that the device powered on.

A successful wake is usually confirmed indirectly when the device reconnects to Lanview Server.

Console commands

Related console commands include:

device.wake <deviceId|machineName>
group.wake <groupId|groupName>
wol.sendmac <macAddress>

Wake-on-LAN runtime configuration commands include:

config.wakeonlanbroadcastaddress
config.wakeonlanbroadcastaddress=<IPv4 address>

config.wakeonlanport
config.wakeonlanport=<port>

config.wakefollowupseconds
config.wakefollowupseconds=<seconds>

config.wakeonlansendmode
config.wakeonlansendmode=<AllEligibleInterfaces|ConfiguredOnly|SourceAddressOnly>

config.wakeonlansourceaddress
config.wakeonlansourceaddress=<IPv4 address>

config.wakeonlanattempts
config.wakeonlanattempts=<count>

config.wakeonlanattemptdelayms
config.wakeonlanattemptdelayms=<milliseconds>

config.wakeonlanalsosendconfiguredbroadcast
config.wakeonlanalsosendconfiguredbroadcast=<true|false>

Enter a configuration command without a value to view the current setting. Enter command=value to update the setting where the signed-in administrator has permission to do so.

Send modes

AllEligibleInterfaces is the default. Lanview Server sends Wake-on-LAN packets through eligible local IPv4 LAN interfaces using calculated subnet broadcast addresses.

ConfiguredOnly sends only to the configured Wake-on-LAN broadcast address. If a Wake-on-LAN source address is configured, the send uses that local IPv4 address.

SourceAddressOnly uses the configured Wake-on-LAN source address and sends to the broadcast address for that source adapter. It can also send to the configured Wake-on-LAN broadcast address when that option is enabled.

Common configuration examples

Default multi-interface behaviour:

config.wakeonlansendmode=AllEligibleInterfaces
config.wakeonlanattempts=3
config.wakeonlanattemptdelayms=250
config.wakeonlanalsosendconfiguredbroadcast=true

Use a specific source adapter:

config.wakeonlansendmode=SourceAddressOnly
config.wakeonlansourceaddress=192.168.1.10
config.wakeonlanalsosendconfiguredbroadcast=true

Use configured broadcast behaviour:

config.wakeonlansendmode=ConfiguredOnly
config.wakeonlanbroadcastaddress=192.168.1.255
config.wakeonlanport=9

Common problems

The device does not wake

Check BIOS/UEFI settings, network adapter settings, power state, switch configuration, subnet routing and whether Wake-on-LAN is supported by the device.

Wake works on one subnet but not another

Broadcast traffic may not cross routers or VLAN boundaries. Configure the correct broadcast behaviour for the network design.

Lanview says the wake request was sent but the device remains offline

This can happen. Sending the packet only confirms the request was made. Device wake confirmation is only recorded when the device reconnects or checks in during the configured follow up period.

Guidance

Use Wake-on-LAN as a convenience and maintenance aid, not as a guaranteed power management system.

Document the network settings required for each site or subnet where Wake-on-LAN is expected to work.