Last reopen vote needed: unix.stackexchange.com/questions/466626/…

@peterh Why? I also don't see how this is on topic.

SU seems like a better home for it.

@peterh The question is not clear to me. Do you want to install another OS using a Linux system? I.e. with the Linux system running?

If so, that should be clearer.

I guess it could be rephrased to "how can I boot off of an ISO that's on my hard drive" but is that really what the OP wants?

I.e. you are trying to install MS Windows from an ISO on a machine using Linux?

If so, I'm really unclear what you expect a Linux system to do in this case.

If you just want to boot off the ISO, there are easier ways of doing this. Like burning the ISO to some suitable installation media.

@FaheemMitha Yes. This is the spec: OP has no USB, ha no CD, he has only an iso image on his Linux. And now he wants to convert his system into a dual-boot one, with his Linux.

@terdon The answer is that he can use that Windows using qemu/virtualbox/vmware with direct partition access. I can't see why wouldn't it be about Linux.

@peterh Wow. Interesting setup. Can't he add a CD/DVD player/writer?

@FaheemMitha No. It might have many reasons, for example if it is on a company machine or if the warranty would be in this case lost.

@peterh If the idea is to run Windows in a VM with a Linux host, the question should say so more explicitly.

@FaheemMitha I've found this problem many times, and it was one of the happiest Linux day as I could install something (maybe reinstalling a company win7) using it as a VM with direct partition access.

@peterh Because that seems more about how to install Windows. Linux is completely incidental to the question. But again, SU seems like a perfect fit. Both Linux and Windows are on topic there after all.

@FaheemMitha The OP asked it Windows-specific, but it is not an essential part of his question. The essential part of the question is Linux-centric.

@peterh "How can I install an operating system in a virtual machine" is linux centric?

@terdon It was already closed, but not with migration reason. Would you please migrate it to there?

Sure

@terdon Yes, how to start vmware/qemu/virtualbox with direct partition access, yes it is very Linux-centric in my opinion.

@terdon Wow! You moved that question!!! Tyvm!!!

You're welcome

@peterh I'm not sure what direct partition access means here.

@FaheemMitha The essence of the correct answer (the already existing answers are false) that the other OS can be installed in a virtual machine, but using a partition of the physical machine as its physical partition.

@peterh Oh. Is that important?

@FaheemMitha Yes. Setting up the boot records/bootloaders correctly, then this installation will be bootable also on the physical machine.

@FaheemMitha Essentially, you converted your system into dual-boot, without rebooting it...

@FaheemMitha This is why I consider this question a wonderful one.

@peterh That seems like a non-answer to me. You're using a virtual machine, you're not actually dual booting. You just tell the VM to use a partition. it seems like a much better approach to have your bootloader boot off of the ISO on your hard drive and then install normally.

@peterh That sounds tricky, and would certainly depend on the VM.

@terdon Can a bootloader boot from an iso image on the filesystem? Can grub do this?

You're depending on your VM behaving transparently. That's not exactly guaranteed.

I've done it, but it was years ago and had trouble last time I tried.

howtogeek.com/196933/…

@FaheemMitha I could do it around 10 years ago first time, with a tricked vmware server. Around 5 years ago it was yet hard to set up, but it went with also others. Today I could do it with minimal configuration trick with virtualbox and qemu, too.

@terdon when using old-style BIOS or CSM it still works, but I think there are issues with UEFI

@FaheemMitha This is a very common scenario if you want to convert a machine to dualboot, and something is not okay (typically, either workplace restrictions or your hw is buggy or warranty on the machine of your friend).

@StephenKitt Ah

@peterh Still, I figure there have got to be easier ways to do it.

Is adding another drive an option? Then you could install it elsewhere and then just plug it in.

@terdon Also I had problems with grub2, it won't boot from hard disks having an LVM volume, without a partition table

@peterh that’s strange, it works like that on my systems, I haven’t had partition tables for years

@StephenKitt I don't think I have had, either.

I've been using LVM on top of a software RAID device for a while now.

Really? I guess I should go with LVM for my next install. I've never used it.

@terdon What do you use?

@StephenKitt I exterminated grub from my system and went back to lilo. As I've seen, Grub wants to have around 30kb binary data behind the MBR, but before the first partition. This setup is essentially incompatible with partitionless LVM hdd-s.

@StephenKitt Btw, are you really using that? If I google for partitionless LVM hard disks, I find only crap, crap and crap. Also the bootloaders and the installers won't admit this setup. In my opinion, the partition table is an ancient fossil and I expel it everywhere, where I can. But I had always the impression that I am alone on the world with this opinion

@FaheemMitha GPT

$ sudo fdisk -l /dev/sda

Disk /dev/sda: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

@peterh I remember having to tweak the setup quite a bit to get it running

@terdon So do I.

but that was a long, long time ago and I don’t remember the details

@FaheemMitha But then you do use partition tables?

GPT is GUID Partition Table

@terdon I don't think so. Let me check my layout.

@StephenKitt Yes. Also I had, and I found the LILO solution. With LILO, I can make it bootable from all of its hard disks, although it requires a major lilo.conf trickery.

Ok, I guess I'm using partitions underneath. Though I never access them directly. E.g.

That's the sort of layout I have.

@terdon Can mods convert comments to answer?

I think one could manage without a partition table if one was going to use the whole disk. Though I'm not sure.

@peterh Nope. Only answers to comments.

@peterh ah I think I’ve found it, see pvcreate --bootloaderareasize

@StephenKitt What does that do?

@terdon Sad, thanks.

There's a feature request for that, I think.

    --bootloaderareasize size
          Create  a  separate  bootloader area of specified size besides PV's data area. The bootloader
          area is an area of reserved space on the PV from which LVM2 will not allocate any extents and
          it's kept untouched. This is primarily aimed for use with bootloaders to embed their own data
          or metadata.  The start of the bootloader area is always aligned,  see  also  --dataalignment
          and  --dataalignmentoffset.  The  bootloader area size may eventually end up increased due to

@StephenKitt Ok, but not clear how this helps with the issue.

@FaheemMitha He was probably answering this:

@FaheemMitha it leaves space for grub’s core.img

github.com/drydenp/grub2-pvinstall

gives more background

@StephenKitt Ah, yes, I see. Is that the same thing as the /boot/efi? I had a separate partition for that.

I find boot manager issues very tiresome. And confusing.

@FaheemMitha that’s a boot partition on GPT

@StephenKitt So not the same thing.

@FaheemMitha right, not the same thing

If anyone smarter at zsh than me knows how to expand an array and add text at the same time, unix.stackexchange.com/a/466844/117549 could use some help

something like "${files[1,5]/prefix-me-with-stuff}" --> prefixFiles1 prefixFiles2 prefixFiles3...

I'm also curious to put my finger on zsh's null-expansion-in-array-assignment that's happening by magic there. I was happily surprised to see it happen, I just couldn't find the zsh man page that described it..

@StephenKitt I used to understand boot issues better, but it's hard to keep things in ones mind if you don't use it.

And of course, all computer concepts gradually become obsolete. Everything we are talking about will seem quaint and old-fashioned in 2040.

@FaheemMitha Hah! You see??? You should reboot more often!

:D ;-) :D

@JeffSchaller found one answer via unix.stackexchange.com/q/258922/117549 -- use prefix${^files}

Added a bounty to my question.

I think it would really be best answered by kernel hackers (or people who hack on containerization).

@Fabby hey

i'm that guy who's too stupid to make the sudoers file to work out for me

:-)

ok... so:

@UTF-8 On the command line, does it ask for a password when running as any user?

only tried my normal user account

should i check a specific other one?

No!

just normal user, not admin user.

@UTF-8 Does it ask for a password?

If yes: my mistake

what do you mean by "admin user"? root or any account that is allowed to switch to root when entering the password?

type

tried it with a different account that is allowed to use sudo with password. same problem

groups

that's an admin user

i'll make a normal account

christoph adm cdrom sudo dip plugdev lpadmin sambashare davfs2 wireshark

ah, so you want to see whether i'm in the "sudo" group?

Tthat's an admin user

Do you want it to work for all admin users?

or all normal users?

this is an admin user:

This is a normal user:

@UTF-8 ah!

Good!

so that's what the script is for: normal user

@Fabby yes, it was executed from my normal account (which is a sudoer). i want it to work on this one

so you want it to work from christoph?

wait, what? do you think it successfully ran that script? it didn't work. it asked the non-privileged user for their password (which there is none cuz i just created that user and didn't set a password)

or from non-privileged-user?

i want it to work from christoph

OK...

but without a password prompt

OK

so it can be run automatically

ok

That's an admin user.

yes

Should it be run from christoph only without password or all admin users?

whatever is easier

OK, lemme check sudoers again

there only are 2 admin users on the system and i'm both of them ^^ it's my personal laptop

thinking.

Gimme 5 min

type sudo visudo

and remove everything you've done in there already

yes

ok

and add at the end:

to the end of the section or to the end of the file?

christoph ALL = NOPASSWD: /mountDropbox.sh

before:

#includedir /etc/sudoers.d

exit terminal

opene new terminal

(no rebooting)

try again.

isn't that a comment anyway?

thank you very much! it worked!! :)

yeah, and before the tuitle too

OK.

Too bad as now your answer is a dupe of another question.

dDeleting answer

when i move it up a bit, it doesn't work anymore

tried the user privileges section again

no!

at the end, last line

1 minute

It doesn't matter from a functionality perspective, but...

@UTF-8 it would be cleaner if you add it on the line before:

# See sudoers(5) for more information on "#include" directives:

#includedir /etc/sudoers.d

also, accept the second duplicate as the answer to your question.

Too bad: no rep for me!

I though I remembered you from Ask Ubuntu and that you were Russian, but now I'm doubting that...

Français?

haha, why are you doubting that i'm russian?

thank you very much for your support! :) i now placed it there

Christoph made me doubt

@UTF-8 Christoph is more of a French name, but I thought I once had a chat with an UTF-8 that was from Moscow.

I'm getting old!

And I NEED A SMOKE!

BRB

@UTF-8 Back.

Anything else?

Hi Nasir. Please leave a comment @Fabby

Going for a smoke. Be back in 5 minutes...