[ydl-gen] recovering from corrupted nvram

[Ed Zaron]

[My apologies if this is a repeat post; I didn't see this in the  
digest.]

Greetings,

To make a long story short, I was trying to install YDL on a PowerMac  
G5 hard drive, with the intent of swapping the drive into a headless  
G5 Xserve of the same vintage.

I installed YDL just fine, but I could not get the PowerMac to boot up  
headless. Eventually, I tried this:

nvsetenv boot-screen enet:0 [ENTER]
nvsetenv console-screen enet:0 [ENTER]
nvsetenv input-device enet:0 [ENTER]
nvsetenv output-device enet:0 [ENTER]

(from http://us.fixstars.com/products/y-hpc/userguide/netboot.shtml)

As you might guess, this did not fix the headless boot issue.

Now the PowerMac turns on but eventually the fans spin up and there is  
no output to the screen. It responds to ping and gets an ip address,  
so it is talking to the dhcp server.

I believe it is still set to boot from the hard disk,
nvsetenv boot-device hd:,\\:yaboot
so I don't think a netboot is possible. But please correct me if I am  
wrong.

Is it possible to send open firmware commands via tftp at this stage,  
or somehow reset the nvram settings? I have tried holding down the  
power button until the long beep. I have also removed the internal  
battery. Unfortunately, these units don't have serial ports (unlike  
the Xserve G5), so I cannot open a serial console.

I gather from extensive googling that booting headless is not possible  
in this case. Or maybe there is a non-public proprietary yaboot patch  
somewhere.

Any suggestions would be appreciated. Fortunately, the G5's original  
disk is intact and fully backed up, but it would be a shame to lose  
this little puppy.

-Ed


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Edward D. Zaron
Senior Research Associate
Hydrodynamic Process and Ecosystems Research Group
Department of Civil and Environmental Engineering
Portland State University
Portland, OR 97207-0751
Phone: (503)-725-2435
FAX: (503)-725-5950
zaron at cecs.pdx.edu
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~