[arch-general] How to install archlinux using a specific parition of usb instead of the whole usb?

[Hongyi Zhao]

Chris Billington via arch-general <arch-general at archlinux.org>
于2019年11月6日周三 下午12:04写道：
>
> You can use multiboot usb to set up multiple distro live images on one usb
> drive:
>
> https://aur.archlinux.org/packages/multibootusb/

I want to use it for booting both live and install images.  It seems
this tool is mainly for live images.


>
> I've used it, it works well. Looks like there's a build issue at the
> moment, but in general it works :p
>
> On Tue., 5 Nov. 2019, 22:50 Hongyi Zhao via arch-general, <
> arch-general at archlinux.org> wrote:
>
> > brent s. <bts at square-r00t.net> 于2019年11月6日周三 上午10:42写道：
> > >
> > > On 11/5/19 9:11 PM, Hongyi Zhao via arch-general wrote:
> > > >>> $ sudo ddrescue -f archlinux-2019.11.01-x86_64.iso /dev/sdc2
> > > >> The ISO contains multiple partitions, so probably not.
> > > >
> > > > Why when using the whole usb disk, the problem will disappear?
> > > >
> > >
> > > As both Eli and I have both explained, because if you use the whole disk
> > > you're writing a partition table as *the partition table for the
> > > device*. If you try to write to a partition, you end up with nested
> > > partition tables. The .iso file is a *disk image*, not a *partition
> > image*.
> > >
> > > >> Why are you
> > > >> trying to do this, precisely?
> > > >
> > > > I want to use a usb disk for installation of multiple distros, say,
> > > > Debian, Ubuntu, Arch, and so on.
> > > > In this case, I must not using the whole usb disk for only one iso,
> > > > and on the other hand, using whole usb disk for only one iso, is
> > > > wasting of the usb's space, considering that we cannot use it for
> > > > doing other things.  Furthermore, I noticed that the dd-based method
> > > > is more robust than using the iso directly with grub's loopback
> > > > module.
> > >
> > > In what way? I do not agree with this. It's far easier to update the
> > > ISO, it's far easier to add new distributions to the bootloader (and
> > > both updating and adding new entries can even be done by regular users
> > > without granting disk reformatting permissions), etc. with grub loopback.
> > >
> > > > To say the least, for the Debian iso, the dd-based method can do the
> > > > trick while the loopback method will fail to detect the cd-rom during
> > > > the installation progress.
> > >
> > > Are you using the appropriate kernel cmdline args in the menu entry?
> > > They're different from Arch's grub loopback menu entry.
> >
> > This is just what I stucked on.  I failed to figure out the correct
> > cmdline args used for linux and initrd.
> >
> > >
> > > https://wiki.debian.org/DebianLive/MultibootISO
> >
> > Useless.  This is for Debian *live* instead of Debian *install* iso,
> > the image I use for install Debian is:
> >
> >
> > http://mirrors.ustc.edu.cn/debian-cd/10.1.0/amd64/iso-dvd/debian-10.1.0-amd64-DVD-1.iso
> >
> >
> >
> > >
> > > >
> > > >>
> > > >> Alternatively, you can use grub to boot an ISO *file* as a loopback
> > > >> device. Some people do this to create multiboot USBs.
> > > >
> > > > As I said above, this method is not so robust as the dd-based method.
> > > >  In detail, the most robust method for using  the usb disk to
> > > > installation a unix/linux OS, should be the dd-based method which
> > > > using the whole usb disk.  But this method has the shortcoming that it
> > > > will occupy the whole usb disk with only a small iso image and
> > > > prohibit us for using the usb disk to do other things at the same
> > > > time.
> > >
> > > This seems highly subjective. What makes using DD superior to a
> > > loopback? It occupies the same exact disk space as if you dd'd to a
> > > partition except requires no modifications to the host disk.
> > >
> > > Now, if you *really* want to save space, you'd extract the squashed
> > > filesystems/initrds/kernels from each ISO you want to add and create
> > > grub entries that boot those directly, but that only affords you a
> > > couple extra megabytes per distribution. However, *that is not what grub
> > > loopback is*. Grub boots an iso file *directly*, with no modifications
> > > required. I guarantee it's far more maintainable and robust than any use
> > > of dd.
> > >
> > > --
> > > brent saner
> > > https://square-r00t.net/
> > > GPG info: https://square-r00t.net/gpg-info
> > >
> >
> >
> > --
> > Hongsheng Zhao <hongyi.zhao at gmail.com>
> > Institute of Semiconductors, Chinese Academy of Sciences
> > GnuPG DSA: 0xD108493
> >



-- 
Hongsheng Zhao <hongyi.zhao at gmail.com>
Institute of Semiconductors, Chinese Academy of Sciences
GnuPG DSA: 0xD108493