I have an existing Debian 9 installation on a 2 TB GPT formatted internal SSD/SATA hybrid hard disk on a brand new Acer laptop. The entire Debian install takes up a mere 600 GB of the hard drive. No other distro nor OSes are on the remaining 1.4 TB space. During the initial Debian installation, I set aside only 250 MB for /boot/efi FAT32 formatted partition which resides on the last partition of my Debian install i.e. /dev/sda7.

On top of Debian, I am thinking of installing several other distros to fill up the remainder 1.4 TB currently empty spaceas well as on an external 2 TB portable drive. I understand that different distros and OSes can share a common, bootbable ESP ala /boot/efi. However going through severalof the Installation guides for Manjaro, Solus among others, I discovered that they mostly seem to recommend a 512 MB /boot/efi. My question is can I simply and safely resize my /dev/sda7 from the existing 250 MB /boot/efi to 512 MB in say, the Manjaro's Calamares (or any other distro's partitioning portion of their installer) installer? Will doing so render my Debian unbootable? What precautions do I need to exercise if any?


2 Answers 2


gparted is a nice way of resizing your disks. It probably won't let you to resize the online root filesystem, so you can create a live usb or cd from their installer, and do the resizing from that live gparted OS (both the EFI and root fs). If there are no problems with operations, everything should work fine.

As to warnings you're asking for, although I've never seen a problem with resizing, that's personal experience and there's always a risk of losing your partition hence data.

Mind you, although I haven't read the howto's you pointed, I didn't think you would need an EFI > 200Mb, but then it changes with how you use it. Actually, my efi didn't work as I wanted and I ended up using my BIOS to choose from multiple EFIs while booting. So here's a thought, you can create a brand new EFI to experiment (or use) on. Just tell your BIOS which EFI you want to boot from (I hope your BIOS will let you).

  • Thank you MattAPriroglu. An example of one of the installation guides is this Manjaro one at wiki.manjaro.org/index.php?title=UEFI_-_Install_Guide . See what it says under Graphical Installer > "For the ESP (EFI system partition) which will store the EFI Grub binary, a 512mb partition of type fat32 can be created in the partitioning step, and mounted to /boot/efi". Commented Jun 30, 2017 at 4:30
  • I'm aware that GParted or the KDE Partition Manager won't allow me to resize a "live" mounted system. I am considering whether I should resize my existing /boot/efi (on /dev/sda7) from 250 MB to 512 MB with cfdisk, gparted or some other similar tool from a System Rescue CD or similar. My current existing partition scheme is here if you or others are interested in having a look: bpaste.net/show/3793079494e8 . As you can see my existing /boot/efi resides on /dev/sda7. Commented Jun 30, 2017 at 4:30
  • 1
    I may consider your suggestion of having multiple /boot/efis for the various other distros that I plan to install on the free space available. I do intend to also have rEFIND installed to manage my multi-booting. Commented Jun 30, 2017 at 4:34
  • It should be fine to extend sda7 to 512M (stealing it from sda6), but since I don't remember myself resizing an EFI partition before, I should suggest creating a new partition, stealing from sda6 again. Of course your current sda7 will be renamed to sda8, which might change some configuration somewhere. I'm still not sure if you really need 512M as the binaries needed are 10-20M max, it's mostly graphics for the rest I guess. You can first try existing EFI as is. Commented Jun 30, 2017 at 4:53
  • 1
    This is what I've decided. The plan goes like this: 1.) Image my /boot/efi, /etc, /var & /usr directories over to a my /dev/sdc 2.) Use a "live" cd/dvd like SystemRescueCD to expand my /boot/efi from the current 250 MB to 512 MB (maybe even 1 GB) using the free, unformatted space after /dev/sda7 i.e. my ESP partition Many thanks MattAPiroglu for your time, patience and advice :). Commented Jun 30, 2017 at 6:59

You shouldn't really need that, and you can create a second "experimental" ESP for those space-hungry distros who throw begamytes at it; also second the rEFInd advice, Rod's books are excellent too. (I've implemented EFI support in ALT Linux, speaking from experience)

  • I actually went ahead with expanding my /boot/efi from the previous 250 MB to the present 1 GB with GParted in SystemRecueCD. It was not without its scare though. The error message informed that GParted wasn't able to resize the FAT32 partition and that they are working on it. However I was able to install Antergos-17.6 and its own grubx64x.efi in /boot/efi/EFI/antergos_grub. Commented Jul 2, 2017 at 10:09
  • That said, I recall seeing a message while using the GParted that comes with the Antergos installer CD saying something to the tune of "unallocated space in the /boot/efi partition" and to select the Check option in one of GParted menu to grow the aforementioned partition. I did as told but as with GParted in SystemRescueCD, GParted again failed with the same error message i.e. that they are working on it. Commented Jul 2, 2017 at 10:10
  • I must add that I did re-enable Secure Boot in my Acer BIOS and get it to recognized Antergos as well as Debian's efis as Trusted sources then disabling Secure Boot again before I was able to successfully boot into either Debian or Antergos. While I seem to have come away somewhat unscathed by the episode, should I be worried about the GParted warnings? Are there or could there be any long-term ramifications? Anyone? Commented Jul 2, 2017 at 10:11

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .