Is it recommended to do automatic partioning in a system with two SSD when installing the OS?

I’ve been having issues with manual partitioning when installing, so I was thinking about selecting the 2 SSD and let the installer do the partitioning, however, I heard that this wasn’t recommended and that it will probably affect my system performance.

Where did you hear that? Unless you have specific needs around storage setup, selecting the default is normally the best.

You can install using automatic partitioning on one SSD and then setup the second one as needed.

You only need to setup everything directly if you want to have your system files on one SSD and the users files on the other for example, as it’s easier to do so during the installation.

There should not be any performance concerns here. If you split your files between different SSDs, performance should go up.

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I’m unaware what the default is when you select two drives in the installer but in case you select to encrypt your drives, and the installer decides to create an LVM volume spanning over two disks, I would recommend not to set up the system like that. The reason is that if one of the two disks fails, your entire LVM fails and all your data is gone, not only data from the failed disk. Also replacing one of the two disks ahead of a hardware failure would be a huge pain.
In case of LVM use, it would be better to set up two separate volume groups and logical volumes.

That’s alot of “in cases”, for a normal use case I would argue choosing LVM is a no go, plus with btrfs it’s useless/of little use (actually get’s in the way IMO). As well, LUKS, how many of us use it? I don’t since I am the only one who access my gear. If I had a situation where I was sharing the gear, I would then think about user level encryption of home and setting a root user at installation time.

I am surprised. In my opinion, encryption should be used wherever feasible, and LVM provides a very simple way to enrypt your data. btrfs alone does not (yet) provide encryption.

I have been using it since LVM and luks containers since a long time, and never had a problem with it. It’s quite flexible and allows for snapshots.

I hope the majority does (talking about desktops, not servers).

That is an optimistic approach. no laptop, no travel, no cross-border crossing, no external, locally stored backup media, PC in a safe, living in a bunker?

Anyway, we should maybe first clarify what anaconda does when you tell it to use two disks (in automatic mode) …

I am doing a Silverblue installation to my Lenovo E530 which has a 256Gb SSD and a 120Gb m2 SSD in it. I selected both drives and reclaimed all space and started the install using automatic partitioning. We shall see what Anaconda does.

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Hello @rhoyzerv , @augenauf and @siosm ,
I can verify that if you select both drives, Anaconda will default to the first available for the install, in this case /dev/sda and leave the second unmounted even though it does delete the data on it if it is selected for reclamation. I hopes this answers your question @rhoyzerv , but if you don’t mind sharing, what is the desired layout you are trying to achieve?

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I was trying to achieve to have my root directory on the 250 GB SSD, and /var on the 1 TB SSD, I tried to do it manually but had problems with turning off the laptop (errors about not finding the partitions to unmount them), now after reading your response I chose to let Anaconda do it automatically for the time being, I don’t mind leaving the second drive unmounted, since I won’t fill my system up to 1TB, however I’m worried about one drive failing and the system completely dying.

In the installer, there is the option to use custom or advanced. If you use the custom, you can specify where to have partitions set. A 256Gb SSD is going to be sufficient for / /var and the ESP as well as the small ext4 partition for the initrd. If you do the default automatic install, then redo the installation this time picking custom partitioning, delete the /home subvolume on the 256Gb device and create a btrfs partition on the 1Tb device then add a subvolume to it that mounts at /home . You can choose to format all the other partitions on the 256Gb drive, just make sure the mount points and layout is the same (minus /home) then proceed with the installation, again. Conversely you can finish the setup of the system after the installation (done by automatic partitioning), and before doing much else you can snapshot your /home subvolume as a read only snapshot and then do a subvolme send/receive with btrfs tools to your 1Tb (btrfs formatted) device. This (snapshot) will then need to be made rw since read only for home is not useful. You then would use the subvolume UUID of your new 1Tb home to modify your /etc/fstab file to have the new subvolume mounted as your home.

Since I’m sometimes on the move with my laptop on me, encryption is necessary to protect my data in case of theft. It was also useful when I sent my device for repair, the worker there contacted me for my password to run diagnostics and verify the system. I refused and told him to boot from another drive/USB or use HP HW diagnostics UEFI. One more reason for disk encryption :slight_smile:

It wouldn’t make your system slower. It may get a little faster in theory if you split files over both SSDs (make the smaller one the root, and use the larger one as /home for example).

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Be careful, this is Silverblue, so most folders are under /var, so use /var/home, etc.

See Installing Fedora Silverblue :: Fedora Docs

Hello @siosm ,
I have personally done this … partitioned my layout as / on one subvolume of a drive with /var on the same device and /home mounted subvolume on another device. All with anaconda during a silverblue install. The home subvolume was already populated with my data so I didn’t want to reformat it. I completed the install with choosing the device with / mounted subvolume and /var mounted subvolume being formated and installed to with my /home remaining untouched. Silverblue hard links the /home subvolume to /var/home and it worked ootb for me. I of course had to change ownership of /home to my newly installed user.

Sorry for the late reply, If I create a / subvolume does /var get created there too? I understood mounting /home on the other device, I will try this setup later today.

If you choose a btrfs volume (ie the root volume) or just choose the devices you want to install to (including the subvolume your home is on) then select advanced partitioning. Select the device with home on it and set the subvolume there to the mount point /home making sure no formatting is selected. Then select the device for the / subvolume and the /var subvolume. If the device already has a btrfs partition created then it is pretty much as follows …

  1. make sure there is an efi partition of adequate size (see installation doc recommendation)
  2. make sure there is a ext4 partition for the initrd, this can be selected to format if desired.
  3. select your btrfs partition and create the two subvolumes on it that will mount at / and /var respectively, formatting is optional but recommended.
  4. make sure your /home subvolume is set up with the correct mount point
  5. select done and it should continue for you.

I have started this process by selecting the one drive that I wanted / and /var on, then picking automatic partitioning and reclaim all space. Continue through install, setup the user, then modify my /etc/fstab to point it to my desired home subvolume, umount /home then mount /home and chown the new home to my freshly setup user.

Thanks! I tried this and It worked like a charm, exactly what I wanted.