# Manual partitioning for installing on SSD with pre-existing Linux OS. Is this steps correct?



## Abraham79 (Aug 25, 2020)

Hi,
I am planning to do a bare-metal installation of FreeBSD 12.1 on a intel 330 SSD which already contain Devuan 3.0 Linux on UEFI-GPT system. I'm planning to install Gnome 3. I tried running the installer and manual mode in bsdinstall seems to me, confusing. It is asking for entire disk or partition. So, I assume shell mode and partition by hand may be better. I created such a scenario of dual booting in qemu-kvm (with virt-manager) with mx linux first installed and FreeBSD later. Tried out below commands to partition the drive (Root is left to fill the free area):

```
gpart add -a 4k -t freebsd-swap -s 1G -l swap0 ada0
gpart add -a 4k -t freebsd-ufs -l freebsd-root0 ada0
newfs -U -L root0 /dev/gpt/freebsd-root0
```
It worked well, at least in qemu.
My queries:

It already contains a EFI system partition created for Devuan Linux. How do I add freebsd boot entries to EFI partition (ada0p1). My understanding is there is no need to create freebsd-boot for EFI installations?
This is a old Intel 330 SSD drive, which is still working great. I'm not sure, if this needs 4k alignment or something like 8k alignment? If 4k alignment is enough?
I am using rEFInd boot manager already. Will rEFInd detect FreeBSD or should manually add the entry.
How do FreeBSD manages TRIM option for SSD? Do I need to set fstrim cron job, like in Devuan?


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