House Keeping Tips for Debian

Tutorials & Resources
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Under the hood, there are a lot of differences, but most of them are especially relevant to advanced/power users. The most obvious difference to everyone beyond beginner level of understanding is that you can create up to 128 primary partitions on the GPT/UEFI scheme as opposed to only 4 with the MBR/BIOS scheme.

To summarize the differences in a single sentence:
The GPT/UEFI scheme is more than 1000 times better than the old MBR/BIOS scheme.

The BIOS or UEFI, respectively, are extremely low level applications, on purpose. Even the full name for BIOS already presents this pretty clearly: Basic Input Output System

Which implies, that you can’t just choose which mode you are using. You have to set your UEFI to boot into the mode you want to use. In your case I would propose to set it to UEFI entirely, by also turning off CSM, which is the compatibility module so that you can use old MBR partitioned HDDs still with a UEFI. It is just for compatability, but if you can you should go for a GPT/UEFI combination. You in your case can, since you are doing a fresh installation anyway and your hardware has a UEFI.

Here’s how to do it:

Prepare HDD to be used with UEFI

  1. Open gParted.
    WARNING: The following operation will seemingly delete the entire selected medium i.e. SSD, HDD…
  2. In the top menu bar select Create Partition Table, choose GPT and confirm.
    The HDD is now ready.

Prepare machine to serve UEFI properly

  1. Reboot your machine.
  2. Enter UEFI by repeatedly presssing F2 or DEL, until you get into the UEFI menu.
  3. Navigate to boot options or whatever it is called on your machine.
  4. Enable UEFI mode, whereever possible.
    WARNING: The following step will disable booting from old MBR based disks, in case you have some in use now that you didn’t prepare as explained above.
  5. Disable CSM. Sometimes this is called something like Legacy Mode or Legacy Support or just Legacy or BIOS compatibility or something like that.
  6. Reboot into your USB medium, that is also UEFI enabled.
  7. Install the distribution, as usual, but this time it will happen in UEFI mode.
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