Configuring wake-up-on-lan on Red Hat

I have a T61 laptop in my office that I use for the following reasons:

1. have access to remotely because it is running the IBM Open Client and in case my laptop running Fedora 20 dies, I still have another alternative.  
2. When people have questions about IBM Open Client I have an place to go.
3. I know I can put IBM Open Client in a KVM but what if my laptop dies?
4. Backup my IBM Notes mail via replication.

Having this computer running full time does not make sense.  I have figured out how to set up the Wake-On-Lan feature on a Windows 7 server at home and it works very well.  The remainder of this blog post describes how I configured the Lenovo T61 running IBM Open Client (RHEL 6.5) to support Wake-On-Lan, a CLI command to put the T61 into suspend state and how to wake up the T61 from a remote server.

Here is a web page that describes how to install and configure WOL for Red Hat. 

The summary of steps (T61):

1. Make sure ethtool is installed: sudo yum install ethtool
2. Write down the interface hardware address (mac address):  Here is a sample of the ifconfig command and associated output.  The HW address is highlighted.

   # ifconfig eth0 eth0      Link encap:Ethernet  HWaddr 00:1B:FC:80:27:17             inet addr:9.10.87.237  Bcast:9.10.87.255  Mask:255.255.255.0           inet6 addr: fe80::21b:fcff:fe80:2717/64 Scope:Link           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1           RX packets:110770824 errors:0 dropped:0 overruns:0 frame:0           TX packets:215059219 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000           RX bytes:10476527981 (9.7 GiB)  TX bytes:321033506529 (298.9 GiB)           Interrupt:16

   
   
3. Verify wake-on-lan is enabled: sudo ethtool eth0.  You should see a value of g in one of the fields from ethtool.  If you do not, use the URL above to fix it.
4. To force server to go into suspend mode: sudo pm-suspend

Note: pm-suspend will hang a terminal ssh session.  I tried doing  "pm-suspend;exit" but that still hung my ssh terminal session.  Perhaps "pm-suspend &; exit" might work better.  Not sure.

From a remote server (not the T61 silly, it should be suspended):

1. The remote server must be on the same IP subnet.
2. Make sure ether-wake command is insalled: sudo yum -y install net-tools
3. Using the hardware address written down from step 2 in the previuos summary, send a wake-up message to the T61: ether-wake -i eth0  00:1B:FC:80:27:17
4. Wait approximately a minute for the T61 RHEL server to complete resuming from suspend mode.  Use ping to verify connection and if ping is successful, ssh or any other remote operation should be operational.