Preparing HDD partitions for dual boot

Question

I've got my Dell Inspirion 5558 with preinstalled Ubuntu 14.04 a few days ago. What I don't like is that the HDD, which has 500GB is not partitioned as I wanted(as expected), so now I have one extra large partition with Ubuntu installed on it, a swap partition and three additional primary partitions made by manufacturer I suppose with boot loader, recovery partition and stuff like that, so right now my hard drive looks like this

HDD(500GB)

• sda1(500MB) - primary, FAT32, label: ESP, flags: boot
• sda2(40MB) - primary, FAT32, label: DIAGS, flags: hidden
• sda3(3GB) - primary, FAT32, label: OS, flags: msftdata
• sda4(454,41GB) - primary, ext4,
• sda5(7,82GB) - logical, linux-swap

First thing I want to know is are there any reasons why I shouldn't erase everything from HDD? I don't know are any of first three partitions required for my lap top to work properly, although I suppose that while reinstalling Ubuntu all that is needed will be created and I really don't think I need a recovery partition as Ubuntu is free to download and use. I don't see the problem with starting from scratch, but as I said I am new to Ubuntu so better safe then sorry right?

Here is what I want. I want to have a dual boot system with Ubuntu 14.04 and Windows 7, but I don't want to install Windows right now. I just want to prepare the HDD partitions so I can reinstall Ubuntu(yes I want to reinstall it actually, so keep in mind that all partitioning will be done while installing Ubuntu) and leave partition for Windows to be installed in the future. Here is the partition scheme that I came up with and which I'd like some of more experienced users to evaluate.

HDD(500GB)

• sda1(150GB) - primary, FAT32, Mount point: none, for Windows
• sda2(30GB) - primary, ext4, Mount point: /
• sda5(120GB) - logical, ext4, Mount point: /home
• sda6(195GB) - logical, FAT32, Mount point: none, for data for both
• sda7(5GB) - logical, swap

Device for boot loader installation: /dev/sda

So here are my questions

1.Should I maybe create another partition(if yes which primary or logical) for boot installation, and how big should it be, or will it be taken care of with this setting? I saw it got 500MB, but only used around 30MB.

2.As I saw I cannot create partition as a NTFS, so I assume I'll have to change FAT32 partitions to NTFS later, perhaps when I install Windows. This is more of an observation then a question really but feel free to correct me if I'm wrong.

3.Are partition sizes OK or should I allocate memory in some other way?

Answer 1

IIRC The only issues Ive ever had with dell laptop hard drives was that their recovery software expected the original drive to be in the machine. For factory restoring the machine it had to be a specific size.

If your machine is using an SSD it may be worth your while to manually partition it with GPT and align your partitions to get a little more speed out of your rig. There are plenty of guides out there for doing that.

1: I think most people create a 500MB boot one these days. IDFK why its just done.. for grub and stuff right?

2: If its an SSD I would leave the windows one as free space for now. Many SSD makers these days automatically use free unpartitioned space as overprovisioning space which improves the drives performance and lifespan. Let windows install to the free space when you go to install it imo.

3: Yes that all looks very nice :). If you are using a spinning disk I would probably tweak the locations slightly so that all the most used data (sda5?) is on the outer edge of the disk to allow for a slightly higher read/write speed. I would also put sda6 between the ubuntu and windows partitions to lower the seek times and put the swap (sda7) right after the most heavily used partition for the same reason.

Answer 2

First, be aware that if you bought a computer with Ubuntu pre-installed on it, the Ubuntu you're running may be customized with special drivers. Thus, re-installing Ubuntu on it might or might not work as well as what you've got now. You should ask the manufacturer, or at least check the PPAs you've got (look for files in /etc/apt/sources.list.d) and be prepared to restore them.

Another point is that it appears your computer is currently booting in EFI mode. Your first partition is an EFI System Partition (ESP), which is required to boot in that way. Pretty much all modern computers use EFI firmware natively, and support BIOS/legacy-mode booting via something called the Compatibility Support Module (CSM), which is a sort of BIOS emulator that runs atop the EFI, sort of like dosemu enables Linux to run DOS programs. If you completely re-do your system, you'll need to decide whether to use BIOS/CSM/legacy-mode or EFI/UEFI-mode booting. The former may be more familiar, but adds complexity to the boot process (see this page of mine for more on this subject). EFI/UEFI mode is the computer's native mode, and it offers some advantages, but it's new, it's got a learning curve attached, and there are still more EFI-mode bugs than BIOS-mode bugs.

Also, be aware that it's best, by a wide margin, to boot both OSes in the same mode. Windows ties its boot mode to its partition table type -- BIOS to MBR and EFI to GPT. Thus, your boot mode determines the partition table type (or vice-versa, depending on your priorities). Given the fact that Microsoft has let Windows' support for extended and logical partitions languish, I'd have to recommend against using MBR with extended and logical partitions; the odds of the Windows installer or some future tool doing serious damage to the setup is just too great. (OTOH, lots of people do run such setups, and if you minimize your use of Windows partitioning tools, you may be able to get away with it. I'm concerned in your case, though, because you want to install Windows after installing Linux, so the Windows installer may try to adjust your partition table, whether you ask it to or not.)

For more on EFI-mode installations, check out:

• Adam Williamson's blog post on how EFI-mode booting works. This is useful theory and background information.
• My page on doing EFI-mode installs of Linux. This moves to more practical tips on how to get it done, but it's not a step-by-step tutorial.
• The Ubuntu community wiki's page on doing EFI-mode installs of Ubuntu. This is a bit chaotic and poorly written at points, but it provides specific procedures for doing an Ubuntu install in EFI mode.