Bonjour Sleep Proxy / WoWLAN / WoL

Power settings, including sleep and wake:

man pmset

What settings are active?

pmset -g

What is keeping your mac awake?

pmset -g assertions

To find out what woke up your mac, run this before sleep:

pmset -g assertionslog

While this is running, you can find out the state of your assertions with CTRL-T

Assertion status system-wide:
   BackgroundTask                 0
   ApplePushServiceTask           0
   UserIsActive                   1
   PreventUserIdleDisplaySleep    0
   PreventSystemSleep             0
   ExternalMedia                  0
   InternalPreventDisplaySleep    1
   PreventUserIdleSystemSleep     0
   NetworkClientActive            0
Listed by owning process:
   pid 97(hidd): [0x0000c79b00099bde] 00:00:00 UserIsActive named: "com.apple.iohideventsystem.queue.tickle.4294971710.3" 
    Timeout will fire in 600 secs Action=TimeoutActionRelease
   pid 56(powerd): [0x0000e37c00108184] 00:01:04 InternalPreventDisplaySleep named: "com.apple.powermanagement.delayDisplayOff" 
    Timeout will fire in 235 secs Action=TimeoutActionTurnOff
No kernel assertions.
Idle sleep preventers: IODisplayWrangler

You'll need to take a look at the internal state of mDNS. To enable debug logging:

sudo killall -USR1 mDNSResponder # so much data.

Trim the logorrhoea to what you came for:

sudo syslog -c mDNSResponder en

Dump the state of mDNS to the syslog:

sudo killall -INFO mDNSResponder; tail -1000f /var/log/system.log

The section “Network Interfaces” in the syslog output lists the network interfaces on your machine that Bonjour knows about. For any interface which (a) Bonjour believes to be capable of Wake On LAN and (b) Bonjour has discovered a Bonjour Sleep Proxy, you should see a black sun (“☀”) immediately preceding the address at the end of the line, like this:

------ Network Interfaces ------
v4 en0(4) 00:17:F2:CD:7E:0A 00:00:00:00:00:00 v4 0.0.0.0 ⊙ ⇆ ☀ 192.168.1.50

For any interface which (a) Bonjour believes to be capable of Wake On LAN but (b) no Sleep Proxy has been discovered yet, you should see a white sun (“☼”). This means that Bonjour is willing to use a Sleep Proxy on this interface, but hasn’t found one yet.

------ Network Interfaces ------
v4 en0(4) 00:17:F2:CD:7E:0A 00:00:00:00:00:00 v4 0.0.0.0 ⊙ ⇆ ☼ 192.168.1.50

Review the canon here.