Hi,

I just finished setting up wake on lan on a couple other computers with different OS's but this is my first time trying with linux and I'm stuck. I've read through tons of posts and articles but no luck.

So far I know that I have wake on lan enabled on my ethernet card and in my bios. When I use "ethtool enp2s0 | grep Wake-on" it shows that wake on lan is set to G. I enabled the PME option in my motherboard and extensively checked through the settings and I'm sure it's enabled there as well.

I believe my ethernet is being powered down and that's probably what the issue is. I tried to disable any form of EEE ethernet but my network card doesn't even show the option to support it. I've read a few other posts and they mention you can edit /etc/rc.d/init.d/halt or /etc/default/halt so that the ethernet card stays powered on after shutdown but I don't have those files. It looks like updates to the OS has changed this.

Does anyone have any idea how I can keep power onto the ethernet card after shutdown? Or how I can modify the shutdown command to do so?

One other thing that I can think of is that WOL on windows machines they have an option called "wol shutdown link speed" and that has to be set to "not speed down" but I don't see anything like that with ethtools.

Would help to know what kind of hardware you're talking about, as in what kind of computer, network card, etc. Hard to speculate without knowing some of the details.

Thanks for pointing that out, I think you're right about the hardware. It does look like it's some type of driver issue. By using journalctl -b I found more info. First my hardware though...

Motherboard: ASUS M3A78-CM
NIC: Realtek RTL8111C Gigabit Ethernet port
CPU: AMD 9550 Phenom
Kernel says.. 3.10.0-957.21.3.el7.x86_64

I think the motherboard is the most relevent part because in journalctl -b I saw this error:
So then I looked through and also saw:
Since it was warning about ACPI drivers.. I updated the firmware on my bios but no difference. I didn't see any useful linux drivers for my motherboard so I'm not sure how to update those. In my BIOS I tried disabling ACPI, and I also tried the extra option ACPI 2.0.. neither made a difference. If it's relevent at all journalctl also said: ACPI: Core revision 20130517.

When I searched the error "System wakeup disabled by ACPI" people suggested checking some OS settings for hardware wakeup and I got the following.. which seems to be fine?

cat /proc/acpi/wakeup
RLAN S4 *enabled pci:0000:02:00.0

But it says S4 not S5 so maybe that's a problem. The system edits this wakeup file constantly so I guess you can't really just edit it directly. Some people also said that /sys/bus/ has a setting that needs to be enabled as well but it says enabled there too...

cat /sys/bus/pci/devices/0000:02:00.0/power/wakeup
enabled

I'm still trying to figure out where my wakeup is being disabled from. I think it's somewhere in the settings of centos. If anyone is able to think of a place I didn't check or give me some more information on any of the following things I'd appreciate it..


I would like to change the /proc/acpi/wakeup file to S5 instead of S4 but I have no idea how, or if I even can. I did read you can edit the file somewhat by using a command like

But this just seems to toggle from enable/disable. I don't know if I can edit the S-state or not.