UBCD architecture / design

Discussion/announcements about test/beta releases of UBCD will be posted here.

Moderators: Icecube, StopSpazzing

Post Reply
Posts: 2
Joined: Wed Sep 21, 2011 6:14 pm

UBCD architecture / design

#1 Post by nezzario » Wed Sep 21, 2011 6:39 pm

Hello all,

My original intentions were to begin building my own 'ultimate' boot CD until I found UBCD. I was, at the time, a little confused on how bootloaders worked on CD's especially when it comes to ISO's.

Well, now I'm even more confused. Kind of. I'm fairly computer adept, my day job is a system administrator for *BSD systems and the occasional debian or CentOS machine, the evening job is a php programmer .. and i'm trying to make the night job a PC repair tech (ok, the day/night isn't entirely accurate, but anyway..)

What I don't understand is the syslinux/isolinux/grub4dos setup. Being that my original intentions was to understand the bootloader concept with ISO/CD's, it really bugs me. I could just drop in custom configurations as per the manual and never think of /what/ I'm actually doing (ok, yeah I get that too, dropping the iso and modifying the bootloader(s) cfg..) but what I'm confused about is WHY is there two bootloaders, that are actually select-able from the first bootloader (which I believe is the sys/isolinux bootloader)?

I mean, I'm asking, why is there two bootloaders which appear to be identical (functionally)? Are the menu's between syslinux/grub4dos actually different in a subtle way, or is it a matter of preference ... or, am I missing something really big? Can one do something the other cannot?

Secondly, I'm confused about the Linux-based tools on the CD. It *appears* to me that *all* the windows (dos) based tools are IN the "fubcd" part, which is a special(how special?) version of FreeDOS.

Then, it appears there are -several- mini linux ramdisk/initrd(kernels) scattered all throughout the disk, and then finally the Parted Magic distro sitting above all. I guess my second line of questioning is: Is this observation anywhere correct, why isn't there a single FreeDOS image and a single Linux image and then commands are ran within these two? I'm not saying your way is wrong, I'm just asking why it is right.

P. S., if any of this is covered in some documentation I missed, much appreciation if you could send a link. Elaboration if the documentation doesn't cover specifically what I'm asking always helps, though!

Regardless, thanks for putting out this awesome collection! :)

Thanks again.

Posts: 1278
Joined: Fri Jan 11, 2008 2:52 pm

Re: UBCD architecture / design

#2 Post by Icecube » Thu Sep 22, 2011 8:19 am

ISOLINUX/SYSLINUX is the default boot loader, but some people prefer grub4dos for their multiboot CD or USB stick.
One reason why the grub4dos menu was introduced, was because some floppy images didn't boot with MEMDISK on some PCs, while they worked fine with grub4dos. This was solved by adding 'raw' to the append line:

Most of the dos-based tools are in fdubcd, but not all. In earlier versions, there was no menu inside the FreeDOS image that showed all programs in categories, so the "correct" program was chosen from the Syslinux menu. Else you had to know the name of the program and type it yourself at the command prompt.
Download Ultimate Boot CD v5.0: http://www.ultimatebootcd.com/download.html
Use Parted Magic for handling all partitioning task: http://partedmagic.com/

Posts: 2
Joined: Wed Sep 21, 2011 6:14 pm

Re: UBCD architecture / design

#3 Post by nezzario » Thu Sep 22, 2011 6:08 pm

So essentially, with the (re?) discovery of the 'raw' parameter in syslinux, grub4dos is fairly obsolete?

I also note that syslinux's website seems to be down. Is this correct, or am I missing something?

Can anyone answer my question why there are multiple Linux kernel/init'rds?

Posts: 832
Joined: Sat May 08, 2010 5:26 am

Re: UBCD architecture / design

#4 Post by ady » Fri Sep 23, 2011 1:19 am

Grub4dos is not "obsolete". For some reason, "some user" may find easier (or more successful) to work with grub4dos, and some other user prefers syslinux. It may depend on the hardware, the tools the user wants to combine and many other things.

Since grub4dos is already in UBCD, there is no need to delete it. Use whichever you want.

About syslinux's website, yes it is currently down (and many other sites related to kernel.org or linux.org are down too, for now).

About the multiple initrd/kernels, UBCD combines several tools. UBCD doesn't use "it's own kernel" or something like that. Each tool is added according to the respective license, with all the relevant files, and if there is any customization is only for some specific reason (compatibility, need, ...). That means that if there are several tools using Linux kernel(s), then they are included, together with the set of files for each tool. Many tools are added "as-is". They simply work, so why change it?

Post Reply