How to install rocky 9.4 without /boot or /boot/efi or any EFI of any kind?

Rocky Linux Tech Help
1

I’ve been working on Linux Mint for quite some time, but now cannot run Blackmagic DaVinci Resolve Studio (because they don’t support it for some strange reason) and require I create a Rocky Linux system.

I have several disks in my system and when I boot up the BIOS (I assume) displays the OS installed on each of the disks and lets me boot from whichever one I want. Most are now Linux Mint v22 but a couple are older versions of Linux Mint.

Now I am trying to create Rocky Linux on the second M.2 nvme in my system. I created a USB for Rocky 9.4 Cinnamon and got to the point where everything was selected except the drive I want to install to. Several times I’ve created 4 partitions for … / swap /home /backup partitions but the install process doesn’t let me continue the install process because … apparently … it demands I create a /boot/efi partition (or maybe just /boot would do … not sure) so it can create some kind of EFI nonsense.

But I struggled to get this computer to NOT have any EFI nonsense so I can select which of the several drives I have in the system to boot from each time I boot up. I am fairly sure that if I create a /boot or /boot/efi partition to install Rocky 9.4 Cinnamon the EFI nonsense will take over the system during boot and I will lose my ability to choose which OS to run each time.

This is what would happen if I create a /boot or /boot/efi partition, won’t it?

So … how can I get this silly installer to install Rocky Linux 9.4 Cinnamon without EFI ???

Thanks.

2

Hi there :slight_smile:

When you boot from the USB flashdrive… do you get two boot options… one for efi boot and one bios boot.
It can be that your hardware boot legacy compatible mode and as you have efi bios it will first boot efi is that is the option. (i always install Legacy mode as that is still king)
I know one of my computers refuse to boot legacy with ventoy even if i trash the install ISO to rip out efi.
So first i will say… check the boot options you get displayed on the bios boot menu.
Second option is to kill efi boot on the ISO/flashdrive.
I made a guide with printscreens about that on Mint forum several years back… what was the thread… it was something with mint 20 legacy boot or bios boot or something… i dont remember…

I just installed Rocky 9.4 Bios mode a few days ago… so its totally doable.
I had to flash to a USB instead of ventoy… and i had to be observant on the bios boot menu, as i got both efi and bios option to boot in to.
Then after install i got a hiccup with booting a black screen, so i had to boot in to “safe mode” then i reinstalled Grub2 and made an update… and now its working.

3

But in some ways, GPT and UEFI (plus grub2) are more flexible than having master boot record. The anaconda installer lets you choose which device to place /boot/efi. It sounds like you’re using the BIOS boot menu to choose o/s, but you can use grub instead.

4

An issue with use of bootloader (GRUB) is that every distro does get updates and has thus a need to update the bootloader’s entries.

Practically every machine today has EFI. Most of them still support legacy mode (aka BIOS boot) too. In EFI setup one chooses whether EFI and/or legacy boot is supported, and for which device types (drives, USB, NIC, etc).

The Rocky installer image does have both EFI and legacy bootloaders set up, so the “BIOS boot menu” can show them both. The installer installes the same mode as it was booted with.

If the EFI mode boot is completely disabled on the EFI setup, then EFI mode boot is not offered to you.

Legacy mode loads first part of bootloader from sector 0. The rest of bootloader is on a filesystem. There used to be limitations on how large that filesystem can be.

The EFI mode loads entire bootloader from EFI System Partition (ESP). The ESP is a FAT filesystem and has directory for each vendor, where that vendor’s bootloader is. Each drive can have one ESP. One could have microsoft, debian, and rockylinux on same ESP, but one cannot have Rocky 8’s and Rocky 9’s bootloader on same ESP (as they would use same directory).

If one has one distro per drive, then each could use either EFI or legacy. The distro’s using the former would have the ESP (that Rocky mounts to /boot/efi) on their drive (or use ESP on some drive).

GRUB does not support LVM. It cannot load kernel and initramfs from LVM. The default partition scheme for Rocky is to have:

  1. FAT ESP (if EFI mode is used)
  2. XFS /boot
  3. LVM PV with LVs for (XFS) /, (XFS) /home, and swap

If you boot in legacy mode, then you could have:

  1. / on “plain” partition

Legacy mode uses “MBR” partition table, which has limit of four partitions (and 2TB size limit). With LVM you can fit the /boot, /, /home, and swap into two partitions.

EFI mode uses “GPT” (as EFI knows how to find the ESP and to read from FAT). GPT supports many more partitions and way larger volumes.

Note: there is no “shrink” for XFS. In order to decrease filesystem size one has to dump data to backup, remove partition, create smaller partition&fs, and restore data.

1 Like
5

Hi jlehtone

I dont know why you addressed this to me. I did not start the thread :wink:

I know i have not written a Bio in here or have been in here so long, so you guys have got to know me a bit more. But i sadly know how computers works… more then i want to know.
It would be nice not knowing IT so when i have problems i can ask a friend to fix it for me. lol :upside_down_face:

6

I will try to address all the replies to my original message in this message.

To provide context and basic information for the folks here who obviously know a great deal more than I do about boot processes, I will now try to insert images of the disks in my system displayed by the linux “disks” application. If someone prefers me to insert equivalent images displayed by the linux “gparted” application I can do that on request. These images were captured and saved with the ALT+printscreen keystroke for each disk.

PS: This forum would not let me insert more than one image. So then I spend about 37 years to figure out how to post them on an internet website and insert links to them. The forum then told me I couldn’t do that either. Great to be a “new user” on this forum — NOT. I wish they had informed me somehow. So finally I had to spend 83 more years to figure out how to insert all the images into one document — a PDF document that hopefully I can insert or attach. If I can insert that PDF document into this message, it contains images of the output of the Linux “disks” application for the drives in the system in the following order from top to bottom.

M.2 nvme0 SSD : 04TB samsung 990 PRO — my usual Linux Mint v22 boot
M.2 nvme1 SSD : 02TB samsung 980 PRO — where i plan to install rocky linux 9.4 cinnamon
SATA HDD sda : 16TB WD 3.5" internal hard disk — appears to contain /boot/efi on 1st partition
SATA HDD sdb : 16TB WD 3.5" internal hard disk — appears to NOT contain any boot
SATA HDD sdc : 08TB seagate 3.5" internal hard disk — appears to NOT contain any boot
SATA HDD sdd : 08TB seagate 3.5" internal hard disk — appears to NOT contain any boot
SATA HDD sde : 02TB external hard disk plugged into computer USB connector
USB3 SSD sdf : 64GB external tiny usb flash drive plugged into computer USB connector

The last (sdf) is the USB flash drive that rocky version 9.4 cinnamon was installed upon
The last (sdf) is the USB flash drive that i tried to install rocky version 9.4 from

This is the PDF file — oops! It won’t let me upload a single PDF file either. :frowning: :frowning: :frowning:

Fortunately I was able to upload the PDF to an image upload site. I’m not 100% certain this will work, but I insert the link below:

images of windows displayed for drives by linux “disks” application

#################################################

#1: It appears that I was wrong. Apparently the /sda HDD contains /boot/efi and the option to boot from many disk drives is displayed at bootup time by that grub boot loader some of you mentioned.

#2: So I guess that means I am not performing “legacy” boot like I thought.

#3: To boot off the Rocky 9.4 Cinnamon USB stick I get into BIOS and select that USB stick to “manually bypass the boot process and boot from that USB stick”. I’m not sure how the BIOS knows to display that USB as a boot option — probably some file on the USB stick, huh?

So, I guess the above information (and perhaps the system information I include below) will help everyone advise me what to do next.

A question. If what I need to do requires I put some EFI file/files/directory/partition on the rocky linux 9.4 cinnamon drive — which will probably be on the 02TB nvme1 M.2 SSD … probably at location nvme1n1p1 ??? … will I need to create a partition for /boot or a partition for /boot/efi ???

I don’t want LVM whatever that is — my memory sucks bad enough as it is, and I don’t want to add yet another set of requirements and interactions that I will never be able to remember or untangle in my brain.

The partitions I want are:

/boot or /boot/efi — only if I must.
/ — the root directory partition … probably 64GB to be safe but no more than 256GB at most.
swap — the swap partition … probably 64GB since my computer has 64GB of DDR5 DRAM.
/home — the home partition … for my personal files including images, videos, C/C++ programs.
/back — a place to let timeshift and/or other backup software put its stuff — 64GB or ?more?

If the above is stupid for some reason, let me know.

I prefer all my partitions be ext4 … again, unless that is stupid for some reason. Maybe the /boot or /boot/efi partition needs to be vfat or fat32 or … you tell me?

I hope the above helps you folks help me … so I can get rocky 9.4 cinnamon installed.

BTW, why is there a Rocky Linux v9.4 Cinnamon ??? Does that have different desktop and GUI applications or something — that look similar to Cinnamon? That would be good for me, since all my Linux Mint drives are indeed Cinnamon flavor.

I really wish I could install Blackmagic DaVinci Resolve Studio 9 on Linux Mint so I don’t need to boot into a totally separate OS to import video files from my Blackmagic camera and edit them. But I guess that’s the reality that I cannot avoid. Though I did order a new GPU with nvidia GPU chips to replace my current GPU based on AMD GPU chips in the hope that might convince the Blackmagic DaVinci Resolve Studio software to function on Linux Mint v22.

If any of you know … will I have to install nvidia drivers before I install the new nvidia GPU card, or will Linux Mint (and rocky 9.4 cinnamon) run with the current AMD drivers after I install the new GPU card? Sigh. What a mess. :-o

PS: Not sure why — maybe because I chose the Cinnamon version of Rocky Linux 9.4 — but I don’t see any indication anywhere that any “legacy” options are offered. Not in the Rocky install file to be downloaded, not while creating the Rocky boot USB from the ISO, not during the installation process, not anywhere that I can see.

Thanks for all your help.

CPU: AMD 7950x
CPU cooler: liquid CPU cooler
DRAM: 64GB DDR5 dynamic ram
GPU: MSI RX 6650XT 128-bit 8GB GDDR6
GPU: ASUS dual GeForce RTX 4060 TI EVO - ordered, arrives 20240910
motherboard: ASUS ROG crosshair x670e extreme
M.2 nvme SSD: 04TB nvme0n1 + 02TB nvme1n1
SATA internal HDD: 2 * 16TB HDD (sda, sdb)
SATA internal HDD: 2 * 08TB HDD (sdc, sdd)
USB external HDD: 1 * 02TB HDD (sde)
USB flash SSD: 1 * 64GB SSD (sdf) == rocky v9.4 cinnamon install SSD flash drive
network: 10Gbps RJ45 ethernet
network: 2.5Gbps RJ45 ethernet
network: wireless ethernet
displays: 43" samsung M70B + 43" samsung M70D
OS: Linux Mint v22 on nvme0n1 is the usual boot drive
OS: Linux Mint v22 and older Linux Mint on some of the 16TB and 08TB HDDs

7

Look at output of lsblk and/or lsblk -f – all text, easier to post than images (that are hard to look at too).

Yes, it (EFI) looks for certain file from certain directory. You should see two USB entries “in BIOS”, if you have enabled both UEFI mode and legacy mode USB boot support “in BIOS”.

I didn’t. I did quote points from your and others’ posts that I elaborated on. The target audience is the OP and basically anyone that happens to see this thread. (It is actually a bit scary to see that some people do read old threads.)

The install image of Rocky has basically options like: Minimal, Workstation, Server. Each install a bit different set of packages. The Minimal is minimal – only CLI. If a set includes GUI, a Desktop Environment", then it is GNOME. There are no other DE in Rocky.

There are “Live images” for convenience that you can boot and run directly from USB. They have various DE, from EPEL repo. These live images do also allow you to install to local drive. I’ve never used live images for that (or pretty much anything else either).

8

When I install Rocky Linux v9.4 Cinnamon and specify my own partitions, it appears I need to create a /boot or /boot/efi partition. Which partition must I create … /boot or /boot/efi ???

9

The UEFI boot requires the ESP filesystem (that is FAT). It will be mounted on /boot/efi.

The content of /boot does not have to be on separate filesystem, if GRUB can read the filesystem that is the /

10

There is one 16TB HDD in the system that has a /boot/efi partition. So I guess you’re saying it is okay for the new Rocky Linux v9.4 Cinnamon install to also have a /boot/efi partition. Correct? I’ve also seen some folks just have a /efi partition instead of a /boot/efi partition … but I guess since that 16TB HDD has /boot/efi they should probably both be the same, namely /boot/efi . Right? Or it doesn’t matter?

BTW, I find it strange to create a partition mounted on something like /boot/efi … because it is not clear how /boot and /boot/efi directories would be related or accessed by the OS. But that’s probably just limited imagination on my part, huh? :slight_smile:

11

You can definitely use a separate /boot partition without necessitating EFI. I have several systems set up like that. I highly recommend that you have a separate boot partition. That way, if for some unforeseen reason your root partition fills up, your boot partition will still be functional and your system will still boot.

I have one computer with EFI. If you don’t like it, you don’t have to use it. You can go into your BIOS and set it up to use the traditional (Master Boot Record) boot procedure instead.

12

Each GPT-drive can have at most one partition with ESP filesystem. This has “nothing” to do with operating systems.

Each operating system may mount any and all filesystems that the machine has (provided that the OS supports filesystem type). Where does OS mount a particular filesystem is up to OS and you. For example, I had PC with three filesystems, which were each a “/” for some OS (CentOS 5, 6, and 7). CentOS 7 mounted its own root as /, and (auto)mounted the other two as /mnt/sysC5 and /mnt/sysC6. That way I was able to access data on 5’s and 6’s “roots” from the 7.

Rocky mounts the ESP to /boot/efi

If /, /boot, and /boot/efi are on three separate filesystems, then OS just needs to mount then in that order. When only / is mounted (and it is the first filesystem to mount), there is empty directory /boot. When the second filesystem is mounted to /boot, we see content of that filesystem under /boot(including empty directory /boot/efi). When the third (ESP) filesystem is mounted to /boot/efi, we see content of that filesystem under /boot/efi.

On a system that has booted with EFI, you can run efibootmgr -v to see what bootloaders the “BIOS” knows to seek from devices.

There is practically no writing to “boot partition” during boot – at most bootloader may try to update “saved” default. Hence “/boot full” is not an issue. When kernel has mounted the ‘/’ (and other filesystems) and services start to write (logs, tmp), the “disk full” can become an issue. (There are embedded or “rootless” systems that write at most to RAM – keep persistent storage read-only.)

13

Yes, that is my point. By keeping a separate boot partition, since it is rarely written to, you can maximize the probability that your operating system will at least always boot. If you reread the initial post to this topic, @inorganic was trying to avoid creating a separate /boot partition.

14

And that is generally not an issue. The /boot being full should not be an issue during boot. The /boot being full while you (attempt to) install new kernel will cause issue for next boot (but should not affect boot with previous kernel).

The / being full would be an issue regardless of /boot being on it or on separate partition.

The /boot not being separate is an issue, if the bootloader cannot load kernel from the /.