In the old days of live isos such as Knoppix ran mostly from cd drives. These days most people will run from a usb drive in some form. Archiso has an option to allow persistence, this means anything done in a session will be saved to a named device. Simply at boot menu hit tab and add ‘cow_device=/dev/sdxN’ (x is used an example and N is a partition number). Once booted you can install modify most of the systems settings including install package (subject to a working network connection).
This is all fine but does have a few drawbacks. You cannot fully update a live system, more to the point you cannot update kernel. You may notice a longer boot time given loading of persistence folder/drive. Have noticed that if I run a newer version of iso current persistence files are not loaded.
A far better option if you want to run a arch system from a portable usb device would be to install arch and run from it.
Am sure it would not be that difficult to use something like this with ArchBang or Project_Vole. This is far better way to go over a poor mans install and would result in a very portable, custom system.
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