Parted Magic and syslinux

[krige]

Hey cheffabe, thanks for the support!

First I tried deleting the partition (I didn't think about that) and setting a new one with gparted (Option: Round to cylinders), repeated the procedure MultiBootUSB installation procedure but that didn't work out either

This is what I have done:

sudo mkfs.vfat -n MultiBootUSB /dev/sdb1
# mkfs.vfat 3.0.7 (24 Dec 2009)

sudo mount /dev/sdb1 /mnt/

sudo grub-install --no-floppy --root-directory=/mnt /dev/sdb
# Installation finished. No error reported.

sudo vim /mnt/boot/grub/grub.cfg

# --- pasted into it the following ---

menuentry "GParted" {
 loopback loop /boot/iso/gparted-live-0.5.2-1.iso
 linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=/boot/iso/gparted-live-0.5.2-1.iso noeject noprompt --
 initrd (loop)/casper/initrd.lz
}
 
menuentry "Parted Magic" {
 loopback loop /boot/iso/pmagic-4.10.iso
 linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=/boot/iso/pmagic-4.10.iso noeject noprompt --
 initrd (loop)/casper/initrd.lz
}

# ---------------------------

sudo mkdir /mnt/boot/iso

sudo cp gparted-live-0.5.2-1.iso /mnt/boot/iso/

sudo cp pmagic-4.10.iso /mnt/boot/iso/

sudo sync

sudo umount /mnt/

[krige]

The Master Boot Record (MBR) partitioning scheme attempts to store partition start and end points in two ways:

• Using a cylinder/head/sector (CHS) triplet, which maxes out at about 8GiB
• Using a logical block addressing (LBA) scheme, which maxes out at 2TiB

The message you note says that these two values don't match. This is most likely caused by either a bug in the original partitioning software or a different interpretation of the disk's CHS geometry (that is, how many cylinders and heads it supports) by the original partitioning software vs. fdisk.

The danger here is that two different OSes or low-level utilities will use different values (one using CHS and the other LBA), or that they'll both use CHS but interpret the CHS geometry differently. The result will be inconsistencies in the start and/or end points of the partition(s) on the disk, which in turn will lead to problems. Most likely the problems would manifest as an inability to mount the partition in one OS, but there could be more serious issues. For instance, an attempt to fix what appears to be a corrupt filesystem because of varying interpretations could end up harming it.

That said, my impression is that most modern OSes favor the LBA values; the CHS values are present mostly for historical purposes. Certainly the CHS values are useless on any disk over 8GiB in size. To completely eliminate the chance of misinterpretation, you could convert the disk to use the GUID Partition Table (GPT) instead of MBR; GPT doesn't use CHS values at all, only LBA values.

Thank you srs5694, both for the explanation and suggestion.

I did what cheffabe suggested: deleted the partition and created a new one with GParted. Now fdisk -l shows the following without any other message:

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1         493     3959991    b  W95 FAT32

Doing this didn't fix my problem though, still it doesn't boot from USB. Do you suggest anyway to try converting the disk to use the GUID Partition Table (GPT) instead of MBR? If yes, how do I do that?

[srs5694]

Doing this didn't fix my problem though, still it doesn't boot from USB. Do you suggest anyway to try converting the disk to use the GUID Partition Table (GPT) instead of MBR? If yes, how do I do that?

I'd forgotten you were trying to create a bootable disk. I know relatively little about syslinux, and in particular I don't know if it's GPT-friendly. I therefore wouldn't try such a conversion unless you research that issue further and find that it should work. If you do, you can use GPT fdisk to do the conversion.

[cheffabe]

I think your grub.cfg is wrong for the stuff your trying to boot. casper? is that for ubuntu itself? I suggest something like this:

menuentry "tinycore" {
 loopback loop /iso/tinycore_2.10.iso
 linux (loop)/bzImage --
 initrd (loop)/tinycore.gz
}

menuentry "pmagic" {
 loopback loop /iso/pmagic-4.10.iso
 linux (loop)/pmagic/bzImage edd=off noapic load_ramdisk=1 prompt_ramdisk=0 rw loglevel=0 vga=791 livemedia noeject max_loop=256 keymap=us
 initrd (loop)/pmagic/initramfs
}

I tested the tinycore one, Im not sure with pmagic. You can remove all kernel options (line starting with linux) for starters. Good Luck. You definitely need to see the grub menu with all your menu entries first in order to verify that grub2 is starting. (Check Bios settings!!)

For the menuentries you can mount the isos and verify the boot options in there.

[oldfred]

I have not yet tested all the Ubuntu versions but all the rest worked- my grub.cfg on my USB key:

menuentry "Ubuntu 10.04 64bit" {
    set isofile="/boot/ISOs/lucid-desktop-amd64.iso"
 
    loopback loop $isofile 
    linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile
    initrd (loop)/casper/initrd.lz
}

menuentry "Ubuntu 9.10 64 bit" {
    set isofile="/boot/ISOs/ubuntu-9.10-desktop-amd64.iso"
 
    loopback loop $isofile 
    linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile quiet splash noprompt --
    initrd (loop)/casper/initrd.lz
}

menuentry " " {
set root= 
}

menuentry "Ubuntu 9.10 32 bit" {
    set isofile="/boot/ISOs/ubuntu-9.10-desktop-i386.iso"
 
    loopback loop $isofile 
    linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile quiet splash noprompt --
    initrd (loop)/casper/initrd.lz
}

menuentry "Ubuntu 9.04 32 bit" {
    set isofile="/boot/ISOs/ubuntu-9.04-desktop-i386.iso"
 
    loopback loop $isofile 
    linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile quiet splash noprompt --
    initrd (loop)/casper/initrd.gz
}

menuentry "Parted Magic" {
    set isofile="/boot/ISOs/pmagic-4.8.iso"

    loopback loop $isofile 
    linux (loop)/pmagic/bzImage iso_filename=$isofile edd=off noapic load_ramdisk=1 prompt_ramdisk=0 rwnomce sleep=10 loglevel=0
    initrd (loop)/pmagic/initramfs
}

menuentry " " {
set root= 
}

menuentry "SystemRescueCd 1.5.0" {
 set isofile="/boot/ISOs/systemrescuecd-x86-1.5.0.iso"
 loopback loop $isofile 
 linux (loop)/isolinux/rescuecd isoloop=$isofile  
 initrd (loop)/isolinux/initram.igz
}

menuentry "Gparted live" {
  insmod loopback
  insmod iso9660
  set gfxpayload=800x600x16, 800x600
  set isofile="/boot/ISOs/gparted-live-0.5.2-1.iso"
  loopback loop $isofile
  linux (loop)/live/vmlinuz boot=live union=aufs noswap noprompt ip=frommedia toram=filesystem.squashfs findiso=$isofile
  initrd (loop)/live/initrd.img
}


menuentry "gparted (Boot ISO Image via Grub2) "{
        set isofile="/boot/ISOs/gparted-live-0.5.2-1.iso"
    loopback loop $isofile 
    linux (loop)/live/vmlinuz live-media=iso=$isofile keyb=us gl_kbd=us gl_lang=en_US gl_numlk=off gl_batch          boot=live union=aufs  toram=filesystem.squashfs noswap noprompt 
    initrd (loop)/live/initrd.img
}

menuentry " " {
set root= 
}

menuentry "Reboot" {
    reboot
}

menuentry "Halt" {
    halt
}

menuentry "Memory test (memtest86+)" {
 linux /boot/memtest86+.bin
}

[C.S.Cameron]

Hey Oldfred:
Did you say the menuentrys for gparted are working for you?
Neither seem to work for me.

Ubuntu goes persistent if I add persistent to the menuentry line as shown below and make a ext2 partition labeled casper-rw.

linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile quiet splash noprompt -- persistent

[drs305]

I just posted a menuentry in the Grub 2 Basics thread this afternoon for booting the ISO from a hard drive. I was using latest version of the Parted Magic ISO and the menuentry is a bit different than what's been posted here. But apparently they all work.

Grub 2 Basics
Section 14.

[oldfred]

My second gparted starts to boot but sees my several root partitions as FAT and gives a UTF-8 error and loops. I did not intend to include that.

The first gparted entry works but I do see a few messages flash by.
this is the one that worked for me:

menuentry "Gparted live" {
insmod loopback
insmod iso9660
set gfxpayload=800x600x16, 800x600
set isofile="/boot/ISOs/gparted-live-0.5.2-1.iso"
loopback loop $isofile
linux (loop)/live/vmlinuz boot=live union=aufs noswap noprompt ip=frommedia toram=filesystem.squashfs findiso=$isofile
initrd (loop)/live/initrd.img
}

[C.S.Cameron]

When I try the gparted script I get:
error: file not found
Press any key to continue...

[oldfred]

IS your path & version correct, I did not use ISO but ISOs and just copied the iso file name to make sure the version was correct?