Sleeping/Waking an Xserve G5?

Question

Level 1

25 points

Sleeping/Waking an Xserve G5?

I've been doing a bunch of testing recently and am having an (interesting) problem trying to get an XServe G5 to wake from sleep. Sleep mode clearly works (as the power light will pulse, as expected), but every mechanism that I use to wake it fails.

Waking with ARD will attempt to start the machine, and fail after 10 or so seconds saying communication failed.

Sending the magic WOL packets through perl scripts, 3rd party tools, and other ways all fail.

Diagnostics:

I have verified that the nodes are (apparently) configured for the Wake-on-LAN access:

root# systemsetup -getwakeonnetworkaccess
Wake On Network Access: On

I have also verified that the magic packets are sent properly using tcpdump to inspect the packets. They are sending the magic sequence properly.

Figuring that the XServe G5 may only listen for WOL packets on en0, I tested only that port. (For what it's worth, en1 also failed the waking process.)

The node can be woken up by pressing the power button quickly. The restore DOES work, just not the WOL portion.

Has anyone had any experience with this problem?

1,750 clustered XServe G5s Mac OS X (10.4.3) 2xDual 2.0Ghz G5 PowerMac, 2.0Ghz MacBook Pro

Posted on Dec 21, 2006 7:38 AM

Reply

Answer 1

Dec 21, 2006 7:54 AM in response to Eric Wages

Are the WOL packets you're sending on the same subnet? I know there are strict limitations on those packets crossing certain network boundaries. (Apple keeps computers running on their campus networks so they can trigger local requests from a central location.)

Just a thought,

=Tod

PS Why do you want the Xserve to sleep? Just curious...

G5/2.0x2, Dual XServes x2, XRAID, beige G3 501Mhz

Reply

Answer 2

Eric Wages Author

Level 1

25 points

Dec 21, 2006 7:58 AM in response to Tod Kuykendall

Yep - nodes are on the same logical (and physical) subnet. I've tried broadcasting the packets to the LAN broadcast address (172.16.255.255) and the generic 255.255.255.255 broadcast address. Both to no luck.

Sleeping and Waking XServes in and HPC environment is quite desirable when you have over 1700 of them 😉 For every watt of power I can save on the floor, that's one less watt of cooling I have to account for at that moment. Let's call it, on-demand compute throttling.

1,750 clustered XServe G5s Mac OS X (10.4.3) 2xDual 2.0Ghz G5 PowerMac, 2.0Ghz MacBook Pro

Reply

Answer 3

rhwalker

Level 3

589 points

Dec 21, 2006 8:21 AM in response to Eric Wages

Sending the magic WOL packets through perl scripts, 3rd
party tools, and other ways all fail.

You don't say what third-party tools you tried, nor whether
any of the methods you tried work on other non-Xserve Macs.

Just for curiosity, so that we know we are starting from a
good test basis, try the free Wake-on-Lan utility:
http://www.readpixel.com/wakeonlan/index.html

I've never tried it on my Xserve G5, but it does work on the
other Macs on our LAN.

Russ

Xserve G5 2.0 GHz 2 GB RAM Mac OS X (10.4.8) Apple Hardware RAID, ATTO UL4D, Exabyte VXA-2 1x10 1u

Reply

Answer 4

Eric Wages Author

Level 1

25 points

Dec 21, 2006 9:59 AM in response to rhwalker

Russ,

Our testing indicates that essentially every other Apple-based system we have can be woken up using the ARD tool and other WOL tools. All do the same thing by sending the magic packet for the machine's MAC address. I've even verified that the Apple-tized MAC addresses (truncating leading zeros) are correctly passed with padded zeros.

I really think that it's something to do with the XServe G5. I've tried this on 2.0, 2.3s. The 2.3s that I tested on have no additional cards in the boxes, and they have stock NVRAM settings.

Reply

Answer 5

Eric Wages Author

Level 1

25 points

Dec 21, 2006 11:05 AM in response to rhwalker

Also, Russ - I tried the tool you mentioned; no go. Just some more fuel for the fire, per se.

Reply

Answer 6

rhwalker

Level 3

589 points

Dec 21, 2006 1:25 PM in response to Eric Wages

Well, that seems to confirm that it's an Xserve G5 issue because
I know that tool works on our other Macs. Sorry I can't test
it here, our Xserve G5 can't be put to sleep - too busy.

Russ

Reply

Answer 7

Eric Wages Author

Level 1

25 points

Dec 21, 2006 1:35 PM in response to rhwalker

Thanks for taking the time to reply. If you ever do get an opportunity to try it, please reply back in this thread - while my request is probably insignificant to most people, it is very important to the operational cost of my facility.

Thanks.

-Eric

Reply