How to format HD for UEFI boot - Centos 7.7

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chlowden007
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How to format HD for UEFI boot - Centos 7.7

Post by chlowden007 » 2020/02/20 08:41:58

Hello
Can someone, please, give me the definitive, bullet proof method for formatting hard drives that is bootable in UEFI mode using the GUI installer? I have a DELL 7530 that only boots in UEFI mode with internal hard drives. Of the 40 reformated installs I have done in the last 4 days, I managed it once, by accident, and have not been able to replicate a method.

I have read all I can find on this; I have tried manually & automatically, but nothing has worked since.
I have a bootable USB stick with centos 7.7 that works, a bios setup in legacy mode with Secure Boot off and I don't want a dual boot or windows installed somewhere.
I am a newby and no terminal master, so I am looking for the idiots guide to formatting.
Thank you

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KernelOops
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Re: How to format HD for UEFI boot - Centos 7.7

Post by KernelOops » 2020/02/20 11:25:44

The most typical setup for me, is this:

Code: Select all

primary partition 1: /boot         500MB          (xfs)
primary partition 2: /boot/efi     500MB          (fat)
primary partition 3: /             remaining size (xfs)
I don't use LVM since there is no need for it in most cases. In servers I use RAID mirrors.

I also don't use swap, I haven't used swap for several decades, because its not really needed for my use cases (servers, desktops whatever).
--
R.I.P. CentOS :cry:
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TrevorH
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Re: How to format HD for UEFI boot - Centos 7.7

Post by TrevorH » 2020/02/20 12:16:57

I do use LVM because it has huge advantages from point of view of flexibility. You will need a separate /boot on a primary partition.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

chlowden007
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Joined: 2020/01/29 07:42:36

Re: How to format HD for UEFI boot - Centos 7.7

Post by chlowden007 » 2020/02/20 16:11:16

I am setting up a desktop machine. Nothing complicated. I have tried many times /boot/efi partition manually but never works on reboot.
How does the machine that it should boot of /boot/efit and not /boot ?
Thank you

chemal
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Re: How to format HD for UEFI boot - Centos 7.7

Post by chemal » 2020/02/20 16:22:04

chlowden007 wrote:
2020/02/20 08:41:58
I have a DELL 7530 that only boots in UEFI mode ...

I have ... a bios setup in legacy mode ...
This is contradictory.

ron7000
Posts: 162
Joined: 2019/01/15 20:00:28

Re: How to format HD for UEFI boot - Centos 7.7

Post by ron7000 » 2020/02/20 16:34:10

KernelOops wrote:
2020/02/20 11:25:44
The most typical setup for me, is this:

Code: Select all

primary partition 1: /boot         500MB          (xfs)
primary partition 2: /boot/efi     500MB          (fat)
primary partition 3: /             remaining size (xfs)
I don't use LVM since there is no need for it in most cases. In servers I use RAID mirrors.

I also don't use swap, I haven't used swap for several decades, because its not really needed for my use cases (servers, desktops whatever).
give me the definitive, bullet proof method for formatting hard drives that is bootable in UEFI mode using the GUI installer
what he said, I use that setup for any hardware supporting efi or uefi including servers.

Apply partition labels to each: I like using boot, efi, root respectively. Helps make things easier later on when being sure what is what when saying to yourself I hope I don't nuke the wrong partition.

I have been doing 1GB for boot, and either 100MB or 200MB for efi. My current 7.7 test system, having been born on 7.6 and has 5 kernel's in the grub boot menu: 1gb boot partition is at 38%, the 100mb efi partition is at 12%.

Also be sure to use a GPT partition table, and not the old MSDOS MBR type partition table.

it was great when ELILO was available (in SLES 11.x). My biggest complaint with Centos/Rhel 7 is the move to GRUB2. Bring back ELILO :cry:
Last edited by ron7000 on 2020/02/20 18:12:20, edited 2 times in total.

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TrevorH
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Re: How to format HD for UEFI boot - Centos 7.7

Post by TrevorH » 2020/02/20 17:27:55

How does the machine that it should boot of /boot/efi and not /boot ?
You need both. The EFI partition must be formatted as an EFI filesystem (it's actually FAT) and must be separate from /boot. Both need to be primary partitions if on a non-GPT disk.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

chlowden007
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Joined: 2020/01/29 07:42:36

Re: How to format HD for UEFI boot - Centos 7.7

Post by chlowden007 » 2020/02/20 18:13:20

What formatting do you use for each partition?
I once found the gui offering an efi format for /boot/efi , but I read that vfat and standard worked. Also, /boot is formatted in xfs. But this is hypothetical as the gui forces start with a lvm format.
Thank you

chlowden007
Posts: 72
Joined: 2020/01/29 07:42:36

Re: How to format HD for UEFI boot - Centos 7.7

Post by chlowden007 » 2020/02/20 18:24:28

Sorry. There was a reply delay.
Do you know what the criteria are to get the efi format to appear the menu?

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TrevorH
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Re: How to format HD for UEFI boot - Centos 7.7

Post by TrevorH » 2020/02/20 18:38:56

LVM is not a format. It's a replacement for partitioning (or an on-top-of). To boot in UEFI mode you must have an EFI partition mounted on /boot/efi and you must also have a /boot though that can be part of / though it's usual to have it separate. The minimum after that is to have one more partition and that can either be a monolithic / containing a single filesystem or you can make that partition into an LVM one that contains (more than one possibly) Logical Volume. You will almost certainly also want a swap area which can be an LV, a partition or even a file. The default filesystem is xfs which supposedly has technical advantages over the alternative of ext4 but also has one major drawback - it cannot be shrunk without a backup/restore cycle.

/boot can be either xfs or ext3 or 4. /boot/efi must be an EFI system partition and if the installer offers that as a choice then it should be used. It is a form of FAT but if there's an EFI listed, choose it.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

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