boot fedora from iso using loopback in grub2

geseeker · #1 31st October 2010, 03:00 PM

Hi, guys! I'm sorry if this question has been answered countless times, but I've searching for answers with no luck. Anyway here's my problem: With ubuntu I'm allowed to boot from an iso image using loopback in grub2, and all I have to do is to pass iso-scan/filename=/xxx.iso to kernel at boot time. The complete grub.cfg looks like this:

menuentry "Ubuntu Maverick" {
loopback loop (hd0,msdos1)/boot/ubuntu-10.10-desktop-i386.iso
linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=/boot/ubuntu-10.10-desktop-i386.iso quiet splash
initrd (loop)/casper/initrd.lz
boot
}

However, fedora doesn't seem to have support for iso-scan, and I've tried isofrom=, findiso=, root=live: with no success. I'm using fedora 13. So is there a way to accomplish this with fedora, or is this feature not supported at all? Thanks.

CSchwangler · #2 31st October 2010, 03:43 PM

You may want to look into this tutorial.

http://forums.fedoraforum.org/showthread.php?t=253292

geseeker · #3 31st October 2010, 04:10 PM

Hi! Thanks for the reply. From what I understand, the method you suggested would require using grub4dos, and it utilises the map command, which is available in grub legacy & grub4dos but not in grub2. This is a great alternative, but I'm already using grub2 to boot iso images so I don't feel like switching to grub4dos.

I'm curious how to use loopback in grub2 to boot fedora iso images.

stevea · #4 31st October 2010, 08:11 PM

https://bugzilla.redhat.com/show_bug.cgi?id=557426

geseeker · #5 1st November 2010, 04:29 PM

Yeah, before posting this thread I've already seen that link you provided. I can't seem to figure out what it says (I don't even know if this particular question has been answered at all). I'm really new to using fedora.

All I want to do is just copying the iso image to the USB disk and boot into fedora using grub2. So what I'm looking for is some kind of kernel parameter (if any exists) that tells the kernel to boot from the iso image provided.

geseeker · #6 4th November 2010, 08:26 AM

So I suppose booting directly from ISO image is not supported by fedora, which is such a convenient feature. This is too bad.

smr54 · #7 4th November 2010, 11:41 AM

This is from the Antix wiki--I have no idea if it would work with Fedora, but...

geseeker · #8 4th November 2010, 04:36 PM

um... what?

smr54 · #9 4th November 2010, 05:52 PM

Oh.....kaay, posting a little too early in the morning

http://antix.mepis.org/index.php?tit...tallation_Tips

mwesten · #10 4th November 2010, 08:44 PM

The tutorial I made is for the DVD only, and I believe you can accomplish the same thing with Grub2. I just find Grub4DOS easier to deal with. AFAIK, the map command in Legacy Grub doesn't support what is needed.

The Fedora LiveCD doesn't appear to have working support for what you seek at this time. However, you could just extract the necessary files from the iso (vmlinuz0, initrd0.img, and the LiveOS directory) and set up a bootloader to use them. It's a bit more work, but I can't think of an application where booting the iso directly would be so much better.

geseeker · #11 5th November 2010, 07:42 AM

Booting directly from ISO image is more convenient, because the only thing to do is to copy ISO to the USB disk and edit grub.cfg. There will also be less files on the USB disk. I'm wondering why iso-scan/ is not built into the fedora kernel.

Anyway, your method suggests using the repo=hd:<device>:/<path> parameter. I looked it up, and found that this will cause it try to look for install.img file in the ISO image, which is not present in LiveCD but only in DVD images.

You said copying the necessary files (vmlinuz0, initrd0.img, LiveOS) to the USB and setting up the bootloader would make this work. So I'm wondering how to set up the bootloader?

mwesten · #12 5th November 2010, 10:45 AM

I understand where you're coming from. That functionality just isn't working yet. See https://bugzilla.redhat.com/show_bug.cgi?id=557426.

What I did for the DVD isn't the best either, but it should work for someone without any other options.

For the LiveCD, this is what I have in menu.lst for Grub4Dos.

Code:

title Fedora 14 LiveCD
root (hd0,0)
kernel /vmlinuz0 root=UUID=088C-85CA rootfstype=auto ro liveimg quiet rhgb rd_NO_LUKS rd_NO_MD rd_NO_DM
initrd /initrd0.img

Change the UUID to match the drive, and that should do it.

tuzza1992 · #13 5th November 2010, 11:31 AM

HI im new to Fedora.... i've got fedora 12 but i cant remember the password for it.. can anyone help me into login in back into the system PLZ. by the way i dont have the CD for it

many thanks

smr54 · #14 5th November 2010, 12:08 PM

Hello tuzza and welcome to the forums. You might want to look at the posting guidelines, as you've made a few mistakes with your post. Firstly, you are doing what is called thread hijacking, posting something that has nothing to do with this thread. Secondly, as this is a pretty common question, you've shown a certain lack of willingness to try searching. Thirdly, you're using text speak (again, see forum guidelines.) Many people will simply ignore a post with PLZ instead of please--you might also view

http://www.catb.org/esr/faqs/smart-questions.html

To answer your question, boot in single user mode and you can then change the password.

If you're not sure how to do that.

http://tinyurl.com/279weyk

Back on topic, I tried booting from ISO on hard drive yesterday. I just used the netinstall iso.

In an Ubuntu intstallation, I created a directory called iso. I copied the iso into it. I then mounted the iso with -o loop and copied over isolinux/vmlinuz and initrd.img to the same directory containing the iso image. So, in my Ubuntu / partition, I have a directory called iso containing F14.iso, initrd.img and vmlinuz.

I then booted into an old Fedora install (that I was planning to overwrite.) The Ubuntu partition was /dev/sda6. So, I added to the old Fedora grub.conf

title Fedora Boot
root (hd0,5)
kernel (hd0,5)/iso/vmlinuz fromiso=/iso/f14.iso
initrd (hd0,5)/iso/initrd.img

It booted and installed without a problem. Haven't tried this with the DVD lately

geseeker · #15 5th November 2010, 04:37 PM

Okay, I figured out how to boot fedora from usb using grub2 (not directly from ISO image though). I used liveusb-creator just to see how things work

, and I figured out the correct boot parameter from syslinux configuration file. mwesten, it's like you suggested:

1. extract LiveOS and EFI to the root of USB flash
2. edit grub.cfg to include this following entry:

Code:

menuentry "Fedora 14 Live" {
    set root=(hd0,msdos1)
    linux /EFI/boot/vmlinuz0 root=live:LABEL="KINGSTON" rootfstype=vfat ro liveimg rhgb rd_NO_LUKS rd_NO_MD rd_NO_DM
    initrd /EFI/boot/initrd0.img
    boot
}

3. restart the computer and boot into fedora live.

ps. on the line root=live:LABEL="KINGSTON", KINGSTON is the partition name of my USB disk.

There seems to be some problems using vmlinuz0 and initrd0.img from the isolinux directory, and I have to use the ones provided in the EFI directory. Maybe they are different?

smr54, I tried your method but it doesn't seem to work. Boot process hangs when it says Signal Caught and sleeping forever. Maybe fromiso is not supported?