[SOLVED] Install from running Fedora system

kibun · #1 21st July 2012, 08:14 PM

Hi all,

I would like to run the fedora installer without the need for any sort of boot media. I already have a Fedora 16 system running from which I would like to install Fedora 17 onto a different hard drive. Is it possible to do this without the use of a USB/DVD live system? I already have the image itself though, that I can use via loop back mount.

Best Regards,
Alex

stoat · #2 21st July 2012, 11:58 PM

Install it from the DVD iso file located in a compatible partition on an accessible hard drive (see the Installation Guide). I haven't done it in a while, but this is generally the way it's done... You can extract vmlinuz and initrd.img from the iso file (or download them). Then load and execute those either from your Fedora 16 boot menu grub prompt, or add a custom entry to your Fedora 16 boot menu to boot them. When Anaconda starts, follow the directions and answer the prompts. I usually put all three files (vmlinuz, initrd.img, and the iso) together in the same place. I recommend they be in the root directory of the partition you chose for them (not in a sub-folder).

kibun · #3 22nd July 2012, 12:02 AM

I tried that, but anaconda never managed to start after the kernel booted. Didn't look much further since the page I read describing that was written for Fedora 9; I figured that booting the initrd directly was no longer supported.

stoat · #4 22nd July 2012, 12:18 AM

Okay. First, I wouldn't read stuff about Fedora 9 to install Fedora 17. Things do change some. For a while there, as an example, we had to copy an /images folder to the hard drive, but that went away recently.

Next, the initrd.img file has always been required to do this. It was never not supported. The kernel needs it to be able to boot.

From a grub> prompt, try these (I didn't test any of this)...

Code:

grub> linux (hdx,y)/vmlinuz
grub> initrd (hdx,y)/initrd.img
grub> boot

You have to figure out what x & y should be.

kibun · #5 22nd July 2012, 12:26 AM

Ahh, yeah, that's what I did (though I made an actual label, not just commands from the grub prompt), and it worked up until I got dropped into a dracut debug shell. Wasn't really sure where to go from there though

. Oh, I should also note, I am using grub 1.95 (from a much older Fedora install), but I assume that probably should not affect the initrd once the kernel has started booting...

stoat · #6 22nd July 2012, 01:39 AM

Try this way...

Code:

grub> linux (hdx,y)/vmlinuz repo=hd:<device>
grub> initrd (hdx,y)/initrd.img
grub> boot

Anaconda will mount and use <device> (e.g., /dev/sda1 or whatever it is for your partition with the iso).

P.S.: I got this syntax from the Fedora 17 Installation Guide. When all else fails, read the instructions, I guess.

kibun · #7 22nd July 2012, 03:20 AM

K, just tried booting the fedora installer from the grub command line; same issue as before. The issue is that the root file system can't be found so I looked at the grub.cfg on the ISO, turns out the config has some strange variabel expansion thing going on. The commands it has are:

Code:

title Fedora 17
        findiso
        kernel @KERNELPATH@ @ROOT@
        initrd @INITRDPATH@

I assume the findiso is irrelevant for booting off a hard drive... Sadly I could not find any definition for the @ROOT@ variable. Maybe if I can figure what this is meant to be, I can pass a correct root= to the kernel and get anaconda up and running.

Any ideas?

***DBelton*** · #8 22nd July 2012, 03:38 AM

might try looking here as well:

http://docs.fedoraproject.org/en-US/...install-hd-x86

stoat · #9 22nd July 2012, 03:41 AM

This works. I just did it myself.

Code:

grub> kernel (hd0,0)/vmlinuz repo=hd:/dev/sda1
grub> initrd (hd0,0)/initrd.img
grub> boot

All three files (vmlinuz, initrd.img, and the iso) were in the root directory of /dev/sda1, an ext3 partition. I used a legacy GRUB prompt to initiate it.

To use GRUB 2 to initiate the installation, substitute linux for the kernel command and use the GRUB 2 syntax for (hdx,y). Those lines also should work as menu entries in an existing GRUB boot loader with the appropriate modifications for the GRUB version.

kibun · #10 22nd July 2012, 05:30 AM

Hmm, interesting link. I will give that a shot.

If it doesn't work I managed to find a squashfs.img file in the LiveOS directory on the ISO. Inside thatr there is a rootfs.img which happens to be an ext4 filesystem with a volume name of Anaconda. If that's not the installer rootfs I would be rather shocked. Maybe I can use that as a root fs from the initrd, hehe. So much indirection...

Edit: I tried using the rootfs image I found as the root device. That boots partially but hangs after a while, I think the last service started was the network. I then tried passing the repo=... command to the kernl but that made no difference. Since I have not yet managed to boot the ISO bootloader without a CD I don't have access to the 'linux' command. Not sure how to hack the ISO image to boot of a disk, but maybe grub can help with that.

---------- Post added at 09:30 PM ---------- Previous post was at 07:47 PM ----------

I abandoned trying to boot the ISO without a DVD and instead realized the obvious solution was to boot the ISO under a VM and use the disk I am trying to install to as the backing disk. I am currently installing, its going slowly

, but it appears to be working.

secipolla · #11 22nd July 2012, 03:23 PM

Hi you can boot fromiso by modifying the initrd: http://forums.fedoraforum.org/showth...hlight=fromiso

Of course, since stoat said he could boot with the original initrd then maybe that's not needed anymore, but it doesn't no harm as I have an entry for Fedora Live (currently is F17 Xfce live-CD) that works just fine.

kibun · #12 22nd July 2012, 04:59 PM

I did roughly the same as what stoat suggested, passing the repo=hd:.. command to the kernel but it still didn't work. Never managed to get to anaconda. I could see some failures in the boot up messages, though I can't remember what they are now. I will continue to try to get the initrd to boot even though I managed my goal already. Is the initrd in a live CD the same as the initrd in an install ISO?

secipolla · #13 22nd July 2012, 05:25 PM

Quote:

Originally Posted by kibun

Is the initrd in a live CD the same as the initrd in an install ISO?

Don't know. I thought all of them were live-CDs (or DVDs).

stoat · #14 22nd July 2012, 10:12 PM

Quote:

Originally Posted by secipolla

Of course, since stoat said he could boot with the original initrd then maybe that's not needed anymore...

Yeah, I could boot with it. But I should take a moment to add more to the record here about the steps I tried above in post #9 to boot and install from the Fedora 17 iso.

True, the steps themselves worked. The kernel loaded. The familiar graphical Anaconda started nicely. I progressed through the language, keyboard, host name, time zone. I created a custom partition layout with a single ext4 root partition because I had only one free partition. Anaconda happily formatted it and moved on to the boot loader page. I changed the boot loader device to the first sector of the Fedora partition because I was not about to let Anaconda put GRUB 2 in my MBR and since I am perfectly capable of booting Fedora other ways. But the moment that I clicked the "Next" button on the boot loader page, an "unhandled exception" occurred and the whole thing stopped. It also happened if I chose not to install GRUB 2 at all.

So at the time, I figured it was just mad at me about either my partition layout or the boot loader selections. I thought surely it would have installed by this method for most other people. But I had to be sure, so I burned the iso to a DVD and tried that thinking surely the same thing would happen. It didn't. There were plenty of bizarre, even flashing, video artifacts while the kernel booted, but Anaconda eventually started and looked great. It smoothly installed the system in my single ext4 partition and with GRUB in the first sector of it.

Therefore...

Something is very wrong with something or other related to the steps I published in post #9 to install from the iso. I tried several times and with various Anaconda boot options, but it never progressed past the boot loader page. I spent some time searching Google for some of the Anaconda debug messaging on the other ttys. Nothing helpful found.

I would love to tinker more with this and get to the bottom of it. But I'm not going to.

I only wanted to make the record clear that the steps I posted in post #9 appear to work initially, but Anaconda would not continue the installation to the end for me. The same iso burned to a DVD installed Fedora 17 without problems.

kibun · #15 22nd July 2012, 11:22 PM

I saw a similar problem when I tried 'yum install'ing anaconda and running it from my normal desktop. Let me reformat my disks and select a custom partition layout but it croaked after there somewhere. My guess is, for now, trying to run the installer without it being on an iso causes anaconda some sort of issue that it can't get around. Maybe its just a simple bug in anaconda? Either way, my method of using a VM allowed me to install fedora without ever having to reboot

. Granted it was very slow... But that did work, if anyone ever wishes to do a similar thing in the future.