This series is written by a representative of the latter group, which is comprised mostly of what might be called "productivity users" (perhaps "tinkerly productivity users?"). Though my lack of training precludes me from writing code or improving anyone else's, I can, nonetheless, try and figure out creative ways of utilizing open source programs. And again, because of my lack of expertise, though I may be capable of deploying open source programs in creative ways, my modest technical acumen hinders me from utilizing those programs in what may be the most optimal ways. The open-source character, then, of this series, consists in my presentation to the community of open source users and programmers of my own crude and halting attempts at accomplishing computing tasks, in the hope that those who are more knowledgeable than me can offer advice, alternatives, and corrections. The desired end result is the discovery, through a communal process, of optimal and/or alternate ways of accomplishing the sorts of tasks that I and other open source productivity users need to perform.

Friday, July 18, 2014

Miscellaneous Friday quickies: The Plop boot manager; what is it and why would you need it?

Prefatory remark: I am uncertain of the licensing status of the project discussed in the posting below, but I suspect it may not--unlike most of the other utilities I discuss in this blog--be open-source.

Unless you, like me, are stubbornly trying to repurpose aging hardware, this tool might not be of much interest to you. But it allowed me to get an older machine booting from USB when BIOS limitations were interfering, , so I decided to document here the fairly simple procedures I followed to accomplish this in case they might be of benefit to others.

How old was said machine? Well, old enough to not only have problems booting from USB flash drives (BIOS USB boot options were limited to USB floppies or ZIP disks), but to have a floppy drive in it as well! A single core machine, as you might guess, although the motherboard did at least have SATA headers--which made it a good candidate for the project I had in mind.

I learned, through some on-line research, about the Plop boot manager--touted for enabling systems to boot from USB even where BIOS settings limited it--and that floppy disk images of the boot manager are included in the download. So I dug up and dusted off a floppy, downloaded the image, and wrote it to the floppy the GNU/Linux way--using dd:

dd if=/path/to/plpbt.img of=/dev/fd0

And that disk did, in fact, allow me to boot sanely from a USB thumb drive I'd plugged into the system. On boot, a starfield simulation reminiscent of the old Star Trek intro (ok, I'm dating myself here) appeared on the screen, in the foreground of which was a boot menu from which I could select the medium I wished to boot. And, sure enough, USB was one of the items.

That wasn't quite all I needed for my own application, however; you see, my hope was to have this machine run headless. So, how to make the boot manager default to booting from the USB drive after a certain number of seconds?

For that, it turns out, I needed another program included in the download called plpbtcfg. That program is what allows one to modify the binary file plpbt.bin. And plpbt.bin needs to be accessed somehow as well in order to modify it--accomplished in my case by mounting plpbt.img as a looped file system.

So I ran mount -o loop /path/to/plpbt.img /mnt/loop. Once that image had been thus mounted, I cd'd to where I'd downloaded plpbtcfg and ran plpcfgbt cnt=on cntval=4 dbt=usb /mnt/loop/plpbt.bin: that gave the boot menu a four-second time count, after which the computer would automatically boot from USB. I rewrote, using dd again, that image, to the floppy. So, mission accomplished.

Except some other aspects of that machine's operation proved not very suitable to the application I was hoping to deploy it for, so I'm not sure it will finally be put into service. But that's another story . . .

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