CentOS - Mar 2021 - Prevent Anaconda from switching root and swap partition

Hi,

More often than not, when installing CentOS, I choose manual partitioning and
then apply the KISS principle, with a very simple partitioning scheme that
looks more or less like this:

  * /boot partition: 500 MB, ext2
  * swap partition: equivalent to amount of RAM
  * root partition: available space, ext4

Now when I do this, Anaconda insists on switching my swap and root partitions,
so instead of this:

  * /dev/sda1: boot partition
  * /dev/sda2: swap partition
  * /dev/sda3: root partition

... I get this:

  * /dev/sda1: boot partition
  * /dev/sda2: root partition
  * /dev/sda3: swap partition

Up until now this hasn't bothered me much. But for my needs right now it
does,
because I need my root partition to be at the end of the disk, so it can be
expanded later on.

Anyone knows how I can prevent Anaconda from switching my root and swap
partitions? What I'm doing right now is switching to a text console with
Ctrl-Alt-F5, manually partition using fdisk, switch back to Anaconda and then
rescan the disk, but it's quite a PITA.

These are the moments where I miss the good old bone-headed Slackware
installer. :o)

Cheers,

Niki
-- 
Microlinux - Solutions informatiques durables
7, place de l'?glise - 30730 Montpezat
Site : https://www.microlinux.fr
Blog : https://blog.microlinux.fr
Mail : info at microlinux.fr
T?l. : 04 66 63 10 32
Mob. : 06 51 80 12 12

> Hi,
>
> More often than not, when installing CentOS, I choose manual partitioning
> and
> then apply the KISS principle, with a very simple partitioning scheme that
> looks more or less like this:
>
>   * /boot partition: 500 MB, ext2
>   * swap partition: equivalent to amount of RAM
>   * root partition: available space, ext4
>
> Now when I do this, Anaconda insists on switching my swap and root
> partitions,
> so instead of this:
>
>   * /dev/sda1: boot partition
>   * /dev/sda2: swap partition
>   * /dev/sda3: root partition
>
> ... I get this:
>
>   * /dev/sda1: boot partition
>   * /dev/sda2: root partition
>   * /dev/sda3: swap partition
>
> Up until now this hasn't bothered me much. But for my needs right now
it
> does,
> because I need my root partition to be at the end of the disk, so it can
> be
> expanded later on.
>
> Anyone knows how I can prevent Anaconda from switching my root and swap
> partitions? What I'm doing right now is switching to a text console
with
> Ctrl-Alt-F5, manually partition using fdisk, switch back to Anaconda and
> then
> rescan the disk, but it's quite a PITA.
That's exactly what I wanted to suggest you :-)

I never found a better way...

Simon

On Wed, 31 Mar 2021 at 05:11, Nicolas Kovacs <info at microlinux.fr>
wrote:
> Hi,
>
> More often than not, when installing CentOS, I choose manual partitioning
> and
> then apply the KISS principle, with a very simple partitioning scheme that
> looks more or less like this:
>
>   * /boot partition: 500 MB, ext2
>   * swap partition: equivalent to amount of RAM
>   * root partition: available space, ext4
>
> Now when I do this, Anaconda insists on switching my swap and root
> partitions,
> so instead of this:
>
>   * /dev/sda1: boot partition
>   * /dev/sda2: swap partition
>   * /dev/sda3: root partition
>
> ... I get this:
>
>   * /dev/sda1: boot partition
>   * /dev/sda2: root partition
>   * /dev/sda3: swap partition
>
> Up until now this hasn't bothered me much. But for my needs right now
it
> does,
> because I need my root partition to be at the end of the disk, so it can be
> expanded later on.
>
> Anyone knows how I can prevent Anaconda from switching my root and swap
> partitions? What I'm doing right now is switching to a text console
with
> Ctrl-Alt-F5, manually partition using fdisk, switch back to Anaconda and
> then
> rescan the disk, but it's quite a PITA.
>
> These are the moments where I miss the good old bone-headed Slackware
> installer. :o)
>
> Cheers,
>
>
Since you are doing manual vs kickstart, you need to do additional steps
Before you go into the disk system in the UI

Control-Alt-F2
fdisk (or gfdisk  or parted depending on your prefs and needs)
clear the disk and set it up how you want it with the types set on each
partition.
go back into the UI and do the things you wanted. have it reread the disks
and have it use the existing partitions versus anything else

Option 2 is to go into the advanced partitioning tool blivet and see if it
can be done through that.. but I think you still need to do a
'slackware/arch' setup first

-- 
Stephen J Smoogen.

On 3/31/21 11:10 AM, Nicolas Kovacs wrote:
> Hi,
> 
> More often than not, when installing CentOS, I choose manual partitioning
and
> then apply the KISS principle, with a very simple partitioning scheme that
> looks more or less like this:
> 
>    * /boot partition: 500 MB, ext2
>    * swap partition: equivalent to amount of RAM
>    * root partition: available space, ext4
> 
> Now when I do this, Anaconda insists on switching my swap and root
partitions,
> so instead of this:
> 
>    * /dev/sda1: boot partition
>    * /dev/sda2: swap partition
>    * /dev/sda3: root partition
> 
> ... I get this:
> 
>    * /dev/sda1: boot partition
>    * /dev/sda2: root partition
>    * /dev/sda3: swap partition
> 
> Up until now this hasn't bothered me much. But for my needs right now
it does,
> because I need my root partition to be at the end of the disk, so it can be
> expanded later on.
> 
> Anyone knows how I can prevent Anaconda from switching my root and swap
> partitions? What I'm doing right now is switching to a text console
with
> Ctrl-Alt-F5, manually partition using fdisk, switch back to Anaconda and
then
> rescan the disk, but it's quite a PITA.
an alternative could be to NOT create any swap partition, and set up a 
swap file instead.
man mkswap
man swapon