Would GRUB bootloader prevent booting from USB drives?

[fuzzybabybunny]

I'm dual-booting Windows 7 and ElementaryOS (Ubuntu). I've got the GNU GRUB bootloader.

My Windows 7 has issues so I need to boot into repair.

Problem is that when I set the BIOS to boot off of the USB drive, nothing happens. It pauses a bit and then boots off the regular hard drive.

I've used Unetbootin and a new 64GB Patriot USB drive to create (what I think are) bootable disks. I've tried ISOs of Windows Repair, Windows 7, and even Hiren's. None of them get my computer to boot off of the USB drive.

Is there a possibility that GRUB is preventing the drive from booting normally?

Is there some kind of secret to making a bootable drive? Does it need to have certain files in the root directory?

 

[ninaholic37]

I found out that some USB flash sticks are not bootable (by design). My 512MB flash stick is (which I use for everything), but the cheap $9 16GB flash sticks I bought were not. UNetbootin should work, or at least it did for me, so I think the problem is probably the Flash stick itself (or possibly the distro you're trying to boot? I dunno, Puppy Linux and FreeDos worked for me on the 512MB one, which I formatted for FAT32 first by right clicking on the drive in Windows I believe).

 

[fuzzybabybunny]

I found out that some USB flash sticks are not bootable (by design). My 512MB flash stick is (which I use for everything), but the cheap $9 16GB flash sticks I bought were not. UNetbootin should work, or at least it did for me, so I think the problem is probably the Flash stick itself (or possibly the distro you're trying to boot? I dunno, Puppy Linux and FreeDos worked for me on the 512MB one, which I formatted for FAT32 first by right clicking on the drive in Windows I believe).

Oof, if that's the case... How do I know if a USB drive is bootable or not? Say, if I run to the store now?

 

[fuzzybabybunny]

Actually I just checked reviews for my flash drive and people are able to use it as bootable media.

 

[ninaholic37]

Actually I just checked reviews for my flash drive and people are able to use it as bootable media.

That's good. I don't think GRUB will block you from booting the USB first though (grub4dos doesn't for me). If the BIOS has the hard drive last, there's no way it can boot into GRUB first before looking at the USB stick in my experience.

 

[fuzzybabybunny]

That's good. I don't think GRUB will block you from booting the USB first though (grub4dos doesn't for me). If the BIOS has the hard drive last, there's no way it can boot into GRUB first before looking at the USB stick in my experience.

Ok. Correct me if I'm understanding the boot process wrong:

- motherboard powers up
- the BIOS gets loaded
- the BIOS settings determine which drive is booted into first
- the BIOS boots this drive and reads some special files on this drive that give further boot instructions
- the bootloader software resides on this drive. Windows installs its own bootloader software but people replace it with GRUB when they want to be able to choose which OS to boot into.
- the bootloader software further handles which OS to boot into (these OS's could be on different partitions on this drive or even in entirely different drives, right?)

Based on the above, if I'm creating a bootable USB disk and it's not booting, the reasons HAVE to be either:

- USB drive issue
- motherboard issue
- motherboard's firmware / BIOS issue

And it has nothing to do with any other drives or OS's or bootloaders, right?

 

[ninaholic37]

Yes! I also managed to boot into USB inside GRUB itself, by adding this to my menu.lst:

# to boot from a USB device
title Boot USB drive
root (hd1,0)
chainloader +1
boot

But I only have one hard drive and no cd-rom, so the hd1,0 and +1 might need modifying for you.

 

[TheELF]

I found out that some USB flash sticks are not bootable (by design).

All flash is created equal...
It's a normal disk and as such has to be partitioned correctly,a lot of manufacturers don't bother doing this.
Have a look at this page.
http://www.eightforums.com/tutorials/15458-uefi-bootable-usb-flash-drive-create-windows.html
This here is the old school way of making a bootable partition.

5. In the elevated command prompt, type the commands below one at a time and press Enter after each one. (see screenshot below)
NOTE: Substitute # in the first command with the actual disk # from step 4 above. For example: select disk 4

select disk #
detail disk (this is to verify that you selected the correct disk before using "clean" below)
clean
create partition primary
format fs=fat32 quick
active
assign
list volume
exit

 

[Essence_of_War]

Yes! I also managed to boot into USB inside GRUB itself, by adding this to my menu.lst:

But I only have one hard drive and no cd-rom, so the hd1,0 and +1 might need modifying for you.

Yeah if there are multiple hard drives it's usually a good idea to use UUIDs not dev numbers, but for your case that should be fine.

It's a normal disk and as such has to be partitioned correctly,a lot of manufacturers don't bother doing this.

I concur, I think this is probably the actual problem. If you're in elementaryOS, if you use 'dd' to write your bootable ISO file to the flash drive:

dd if=/path/to/iso of=/dev/sdX bs=1M

where "X" is the usb device letter that you can find from either fdisk, gparted, or whatever disk partitioning tool elementaryOS comes with. If your BIOS boot options are set to boot from USB, and the ISO is bootable, and there are no issues with the USB port in question, that should boot instead of loading GRUB.

 

[ninaholic37]

Very interesting, about the "all flash drives are bootable" thing.

I did manage to boot into my 16GB Flash drives from the GRUB menu, so I guess I'll chalk my previous attempts of a true boot (and all other claims I've heard of certain flash sticks working while certain other ones not) to "user error" or "missing step somewhere" or "it must be possible somehow"... unless I find any more info to the contrary.

 

[kommisar]

I'm dual-booting Windows 7 and ElementaryOS (Ubuntu). I've got the GNU GRUB bootloader.

Problem is that when I set the BIOS to boot off of the USB drive, nothing happens. It pauses a bit and then boots off the regular hard drive.

I've used Unetbootin and a new 64GB Patriot USB drive to create (what I think are) bootable disks. I've tried ISOs of Windows Repair, Windows 7, and even Hiren's. None of them get my computer to boot off of the USB drive.

I have had laptops that had problems booting larger usb drives because there were bugs in the bios. Frex, an elitebook 8540w with an early bios would hang when booting 32GB sticks. The later bios apparently fixed this problem but I tried a 128GB stick and it wouldn't boot while a 16GB stick prepared by the exact same method would. So its possible bios bugs are causing your boot problems. Try a 16GB or 8GB stick prepared in the same fashion to see if this is happening.

 

[VirtualLarry]

All flash is created equal...
It's a normal disk and as such has to be partitioned correctly,a lot of manufacturers don't bother doing this.
Have a look at this page.
http://www.eightforums.com/tutorials/15458-uefi-bootable-usb-flash-drive-create-windows.html
This here is the old school way of making a bootable partition.

Except... they're not. Some USB flash drives show up as "Removable USB drive", and some show up as "USB HDD" in BIOS. Are you suggesting, that the partition type determines that, and not the flash drive? Because I've read things about controller bits and special mfg utilities for configuring said bit.

I have had laptops that had problems booting larger usb drives because there were bugs in the bios.
So its possible bios bugs are causing your boot problems.

Very true.

 

[fuzzybabybunny]

Guhhh I still can't boot into any USB drive. I bought a small 8GB and have a 64GB and neither boots. I've created the boot disk using unetbootin, Windows, virtualdrive. Should I try downgrading my BIOS? It's the latest version for my Asus UX32VD.

 

[TheELF]

Are you suggesting, that the partition type determines that, and not the flash drive?

I am saying that a usb has to be made bootable just like any hdd(back in the days) ,by creating a primary partition and making it active which will create a bootblock.

 

[TheELF]

Guhhh I still can't boot into any USB drive. I bought a small 8GB and have a 64GB and neither boots. I've created the boot disk using unetbootin, Windows, virtualdrive. Should I try downgrading my BIOS? It's the latest version for my Asus UX32VD.

Try with microsoft's own tool,it's supposed to do everything necessary on its own.
https://www.microsoft.com/en-us/download/windows-usb-dvd-download-tool#installation

 

[Red Squirrel]

I noticed that since the introduction of UEFI, POSTing can be really weird at times, it's almost like it sometimes decides to skip certain steps and the previous shutdown/restart never actually took place and the previous OS is still in memory and takes a few tries to finally get to the boot menu or to get something to boot the way you want. Sometimes shutting down the machine completely and turning off the PSU power switch off and back on will help. Mind you I've seen this phenomenon more with laptops. Trying to boot a USB stick on a windows 8 machine and it keeps going back to the 8 desktop as if I never even shut it down, for example.

Though one thing that irks me is that not all mobos use delete as the standard way in the bios, and bios splash screens are too fast now to see the key on time. What's probably happening is that USB removable device is not set to boot before the hard drive so you may have to change the order. On certain motherboards I find even that is not enough, you need to hit water key is for the boot menu and then manually select it, it may take several tries to see what that key is because of how fast it flashes by. It's usually one of the F keys like F2.

 

[jhu]

Guhhh I still can't boot into any USB drive. I bought a small 8GB and have a 64GB and neither boots. I've created the boot disk using unetbootin, Windows, virtualdrive. Should I try downgrading my BIOS? It's the latest version for my Asus UX32VD.

Try removing the hard drive. If the USB stick still doesn't boot (but does boot with another computer), then it's likely a firmware/hardware issue.