One pendrive for all PC (Intel/AMD) computers - single-boot dual-boot multi-boot

[sudodus]

You will be able to manage the daily build iso files of the Ubuntu family flavours, to install and update them incrementally directly in the pendrive, which saves time and effort. So a 'grub-n-iso' pendrive with the shell-scripts links2check and links2update should be a convenient tools for all our iso-testers as well as for other people who want to try the bleeding edge version.

Manage the daily built iso files of your choice

Notice that a pendrive with this system can be upgraded directly. So you get the upgrade directly from the Ubuntu server to the pendrive without a detour to a hard disk drive. Of course you have to reboot to test/use the new version, but this direct method is convenient and saves time. Pendrives are often slow, and I have found that rsync behaves much better than zsync, when the target drive for updating is a pendrive. (So this system uses rsync instead of zsync, that seemed better at first glance.)

One big advantage is that there is no need for copying/cloning/flashing from the internal drive to the pendrive. The slowness of the internet connection matches quite well the slowness of a USB 2 connection, so you don't lose much time anyway.

When installed and running from the 'grub-n-iso' pendrive, change directory to /isodevice and run links2check to create and maintain the system. You arrive at the main (zenity) menu. See attachment #1, where you can select a flavour (in this case Ubuntu). After that you arrive at the iso file menu, where you select architecture (in this case 64-bit). See attachment #2. You can follow the process in the terminal window, how the MD5SUMS file is downloaded, and used, but there is no iso file yet. Then rsync starts downloading the iso file and finally it is checked with md5sum.

cd /isodevice
sudo -H ./links2check
sudo -H ./links2update

Starting from the compressed image file dd_lubu-14.04.2-desktop-i386_isotest1_7.8GB.img.xz and running a persistent live session, you are helped by some tweaks, that are prepared and saved in the casper-rw file, so that you arrive easily in the directory /isodevice and can start managing the ISO files.

links2update makes daily updating of the ISO files easy. There is only one (zenity) menu, and you select one file or all files to update.

But you are not ready yet. You should also link to the targets in the current directory. Start links2check again and select the first or last line for this linking mode. See attachment #3. There is also output text in the terminal window (similar to the following example).

$ sudo -H ./links2check 
Using template 'grub.cfg' in the current directory
'ubuntu-wily-desktop-amd64.iso' -> 'cdimage.ubuntu.com/daily-live/current/wily-desktop-amd64.iso'
1 linked daily iso file(s)   - with grub menuentries
1 linked regular iso file(s) - with grub menuentries
0 iso file(s) that cannot be booted by the 'grub-n-iso' method
$

There are grub menuentries for two iso files, the original 'Lubuntu-14.04.2-desktop-i386.iso' and the new 'Ubuntu-wily-desktop-amd64.iso'. The file grub-final.cfg is copied automatically to the active boot directory.

sudo cp grub-final.cfg 'mountpoint'/boot/grub/grub.cfg

set timeout=10
set default=0

menuentry "Lubuntu-14.04.2-desktop-i386.iso - live" {
 set root=(hd0,2)
 loopback loop /lubuntu-14.04.2-desktop-i386.iso
 linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=/lubuntu-14.04.2-desktop-i386.iso splash --
 initrd (loop)/casper/initrd.lz
}
menuentry "Lubuntu-14.04.2-desktop-i386.iso - persistent live" {
 set root=(hd0,2)
 loopback loop /lubuntu-14.04.2-desktop-i386.iso
 linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=/lubuntu-14.04.2-desktop-i386.iso splash persistent -- persistent
 initrd (loop)/casper/initrd.lz
}

menuentry "Ubuntu-wily-desktop-amd64.iso - live" {
 set root=(hd0,2)
 loopback loop /cdimage.ubuntu.com/daily-live/current/wily-desktop-amd64.iso
 linux (loop)/casper/vmlinuz.efi boot=casper iso-scan/filename=/cdimage.ubuntu.com/daily-live/current/wily-desktop-amd64.iso splash --
 initrd (loop)/casper/initrd.lz
}
menuentry "Ubuntu-wily-desktop-amd64.iso - persistent live" {
 set root=(hd0,2)
 loopback loop /cdimage.ubuntu.com/daily-live/current/wily-desktop-amd64.iso
 linux (loop)/casper/vmlinuz.efi boot=casper iso-scan/filename=/cdimage.ubuntu.com/daily-live/current/wily-desktop-amd64.iso splash persistent -- persistent
 initrd (loop)/casper/initrd.lz
}

The next time you boot, there will be grub menu items also for the Ubuntu wily daily build (according to this example).

Use links2update to let rsync update the iso file the next day or later, when you have time again to test your favourite Ubuntu flavour daily iso file(s).

Use mkusb-nox to install from the Ubuntu Server and Lubuntu alternate iso files, that do not boot via grub.

[sudodus]

Comments and tips

Where does it work?

Post #1. One pendrive for all PC (Intel/AMD) computers - Ubuntu 64-bit and Lubuntu 32-bit

Ubuntu 64-bit works in BIOS and UEFI mode, also with secure boot. Lubuntu 32-bit works with 32-bit and 64-bit computer hardware, so it adds ability to boot 32-bit computers including old hardware.

The posts #(6, 7, 8, 10, 11) describe 'grub-n-iso' systems, that can boot 32-bit and 64-bit Ubuntu family operating systems in BIOS and UEFI mode, but these 'grub-n-iso' systems do not work with secure boot.

Ramdrive

Using the boot option toram makes it possible to unmount the mounted partition(s) on the boot drive, and it can be removed. toram makes the system copy all of the content from the squashfs to RAM, so the boot process is slower, but after that the system is very fast and responsive.

If you haven't got enough RAM, there can be problems, otherwise it works very well.

casper-rw and home-rw

A casper-rw partition is standard for persistence. C.S.Cameron suggests casper-rw + home-rw partitions, and it is even better, particularly if you have plenty of space in the pendrive or where you keep the partitions for persistence, because the home-rw partition will probably survive even if the casper-rw partition is damaged.

[sudodus]

'grub-n-iso' works also with a Linux Mint 17 iso file

I downloaded linuxmint-17.2-cinnamon-64bit.iso, copied it to a 'grub-n-iso' pendrive and ran

cd /isodevice
sudo -H ./links2check

selected 'Link to targets in the current directory'

and rebooted. It worked without tweaks, and now I know that the 'grub-n-iso' system according to this thread works also with current Linux Mint iso files.

[sudodus]

New features in a new compressed file for a 'grub-n-iso' system to manage iso-testing

The compressed image file dd_lubu-14.04.2-desktop-i386_isotest1_7.8GB.img.xz contains some tweaks. They are activated if you run a persistent live session, so that you arrive easily in the directory /isodevice and can start managing the ISO files.

You start with links2check but the new script links2update makes daily updating of the ISO files easier than before.

-o-

I have found that you can have more than one set of persistence in the casper-rw partition. You start with persistence for a released system Lubuntu 14.04.2 LTS.

After that you install one or more daily build flavours of Ubuntu (when this is written it is the version Wily). If you boot Wily with persistence, it will be stored in

.../casper-rw/upper

and will not interfere with Lubuntu 14.04.2 LTS, which is stored in

/casper-rw

But the different flavours of Ubuntu Wily will interfere with each other, which is no problem for data files, but if you test both 32-bit and 64-bit versions and install or update program packages, where 32-bit versions are different from 64-bit versions, there can be big problems. So it is a good idea to back up the content of the casper-rw file, for example in a tarball.

[sudodus]

During iso-testing of Lubuntu Wily alpha 2, I booted the installer via this 'grub-n-iso' method. It seems to have confused the alternatives of the installer for automatic selection: I did not get any option to 'Install alongside and auto-resize', only upgrade 14.04.2 LTS, erase 14.04.2 LTS, erase the whole drive, and 'something else'. It was not possible to run the testcase 'Install (auto-resize)'.

Bug #1479405 affects booting via 'grub-n-iso', while booting from a pendrive made with mkusb brings 'Install alongside with auto-resize'.

The other alternatives of the installer (ubiquity) work as they should when booted via 'grub-n-iso'.

[sudodus]

@ ventrical,

What about the attached screenshots of mkusb windows? (Legacy is the fallback when zenity is not compiled with webkit, so there is no rendering of html).

1. Do you suggest further changes to some of these four windows?

2. Is there any more window, where you think that the text should be changed?

-o-

I intend to move moved this dialogue to the thread where it belongs, Howto make USB boot drives except this post - with a link to help you find the new location.

[Dkaz]

@ Sudodus

I'm a newbie to Linux as a whole so I want to start by thanking you for the detailed guides . I am currently dual booting Windows 7 and Ubuntu on my secondary laptop. I was wondering if it is possible/bad/ok/whatever to have more than just those 2 operating systems. Per se, could I trio boot my current setup plus Linux Mint? If so, would I just go through the normal installation process like I was setting up a dual boot? I am going into college in the fall as a computer engineering student so I'm trying to broaden my horizons as much as possible. Thanks!

[sammiev]

@ Sudodus

I'm a newbie to Linux as a whole so I want to start by thanking you for the detailed guides . I am currently dual booting Windows 7 and Ubuntu on my secondary laptop. I was wondering if it is possible/bad/ok/whatever to have more than just those 2 operating systems. Per se, could I trio boot my current setup plus Linux Mint? If so, would I just go through the normal installation process like I was setting up a dual boot? I am going into college in the fall as a computer engineering student so I'm trying to broaden my horizons as much as possible. Thanks!

I had many OS on one laptop with little issues.

If you have the room it can be done.

As always, backup any or all data.

[sudodus]

Welcome to the Ubuntu Forums

+1 (I confirm the reply by sammiev.)

You can install many linux distros/versions in the same computer (in the same or different internal or external drives). I suggest that you

0. backup your current systems, because things can go wrong,

1. boot a live session from the install DVD/USB drive,

2. edit the partitions with gparted before you start installing. This way you can 'see' what you are doing in the graphical user interface, so that you get a good structure and suitable sizes of the partitions. Maybe 8 GB is minimum size for testing a distro and 20 GB to run it and have some space for new program packages and various data files. You can share the swap file unless you want to hibernate the systems. It is a good idea to have a common data partition. Since you have Windows, the data partition should have the NTFS file system (because Windows does not read linux file systems). Do not write from linux into the system partition of Windows, C:

3. run the installer and install the third system into the partitions you have prepared. Use manual partitioning: select Something else at the partitioning window.

[Dkaz]

Thanks for the info! Got it working