I executed a "complete" Ubuntu installation on my USB stick – not burning a persistent LiveCD onto it, but instead using 2 USB sticks, one containing the LiveCD and the other as the destination (the bootloader was also installed on the destination stick).
Now, during the installation, I noticed that the wizard configures some hardware-related elements. Does this mean that such installations are limited to run on the same machine as where the install wizard is executed? If yes, 1) what will happen if I take this stick elsewhere and try booting it on another hardware, and 2) is there a way to overcome that, so I can both avoid LiveCD+persistent (because persistent space is limited), and have a universal installation?
Best Answer
A portable installed system, that boots both in UEFI and BIOS mode is described in this link,
Installed system that boots from UEFI and BIOS mode
There are more details at the following link,
help.ubuntu.com/community/Installation/UEFI-and-BIOS
Q: Now, during the installation, I noticed that the wizard configures some hardware-related elements. Does this mean that such installations are limited to run on the same machine as where the install wizard is executed?
A: No. It is portable, but not as portable as a persistent live drive.
Q: ... because persistent space is limited.
A: You can store the persistence in a partition, which is limited only by the size of the drive. With a GUID partition table (GPT) it can be several terabytes. mkusb can install such persistent live systems.
Comments: But there are other drawbacks with a persistent live system. It is less stable compared to an installed system, and you cannot use a new kernel because the kernel is started before the overlay for persistence is started. Also, I would recommend to install program packages, but not update and upgrade the persistent live system. Instead you should install a new persistent live system from a current iso file.
See also the following links,
askubuntu.com/questions/936633/ubuntu-live-from-usb-with-full-persistence-and-ntfs/936641#936641
Persistent live versus installed Ubuntu in the USB flash drive
Try Ubuntu (Kubuntu, Lubuntu, Xubuntu, ...) before installing it
Edit: A USB 3 SSD flash drive has much faster flash hardware than a standard USB pendrive, and there are USB 3 pendrives with specified high read/write performance. The market changes, so it is worth checking on the internet, which brand and model to select to get the best buy 'today'. See this link about fast USB 3 pendrives,
help.ubuntu.com/community/Installation/FromUSBStick#Notes_about_speed