Provide a method for installing Ubuntu directly into an USB drive

[Alberto Salvia Novella]

Most important bugs that people experience when upgrading Ubuntu are hardware related, and that's because Ubuntu is mostly tested using virtual machines.

We need a method that would allow to install daily images directly into USB drives, without needing to use persistence. Just as it was a hard disk.

I tried doing so by using Ubiquity, the Ubuntu Live CD installer, but it crashes as per bug #1687332. Anyway that method isn't agile enough, as after installation you would have to upgrade to the development release anyway.

Implementing this feature could save a big amount of crashes after release, allowing people to easily test their hardware in advance and having the developers time to fix them.

[Brian Murray (brian-murray)]

Why would you "have to upgrade to the development release" after installing a daily Live CD? A daily Live CD is the development release of Ubuntu.

[Alberto Salvia Novella (es20490446e)]

@ Brian Murray

I mean using the method in bug #1687332, which is using Ubiquity on a production system to create a development installation in an USB drive.

[sudodus (nio-wiklund)]

It is straightforward to use zsync to keep the daily iso files up to date. There are links at http://iso.qa.ubuntu.com/

This way you need only download the differences between yesterday's and today's iso files. And the iso files are checked automatically by zsync.

Then you can use the daily iso files to install systems into external drives. A 64-bit Ubuntu iso file makes a DVD/USB drive that boots in BIOS and UEFI mode. The installed system will boot in the mode, that was running when you installed it.

There is a problem is with the bootloader. Installing the bootloader is flexible (but somewhat risky) in BIOS mode. In UEFI mode the bootloader will go to the internal drive['s EFI partition] whatever you specify unless you disconnect the internal drive.

To make the computer available for safe testing, I would recommend to disconnect (unplug) the internal drive and have the production system in an external box (for example an SSD in a box with USB3 or eSATA connection).

[Lyn Perrine (walterorlin)]

I have for a while been dual booting a stable install alongside a development install even on external drives. This does not have the grub panicing if a drive is missing in bios mode with a missing drive and goes into recovery mode with even less options. Granted the choosing wrong partition can be a problem with catostrophic results. Although I am not sure this is good for others but I memorize which partition not to touch.

Also hardware affecting bugs can happen in the installer but maybe not as often see bug #1675127 which has quite specific of not being connected over ethernet and have a broadcom 4322 that the installer sees and does not have drivers for in every ubuntu release I have used except the broadcom proprietary ones.

[Alberto Salvia Novella (es20490446e)]

Thanks for the info.

I think the easiest solution is having the internal drive with the stable Ubuntu release for production, and having the development release in a pen drive. Then configuring the BIOS to boot from the pen drive first if connected, so for testing you only have to plug it in.

And if you want to keep the image upgraded, you only have to upgrade from the Terminal.

Perhaps I shall document that.

[Filiberto (fili-biolcatirinaldi)]

How much should be the storage of the pen drive where we can install the ISO? Is it enough 4 GB?

[sudodus (nio-wiklund)]

@Filiberto,

For a live-only pendrive and a persistent live pendrive 4 GB is enough. But you may want at least 8 GB (better a fast USB 3 pendrive with 16 GB) for a persistent live drive.

For an installed system at least 8 GB is necessary for testing. For real usage you need at least 16 GB (space to install application programs and data files). And it makes a real difference to have a fast USB 3 pendrive. Otherwise the installed system will be slow.

See this link,

https://help.ubuntu.com/community/Installation/FromUSBStick#Prerequisites