What partitions should I create for Ubuntu on a 1 TB hard drive if I ultimately want to install 3 Linux distros on it and share files between them?

Question

I am looking at partitioning a new hard drive and I am not sure on how to go about it.

The drive that I am installing Linux on is 1 TB and I would like to separately partition for my / and /home. I have googled a bit and seen suggestions for the /tmp, /usr, and /var directories to be on separate partitions and would appreciate any information on the benefits and ballpark figures on the sizes required. I know that the swap needs to be a primary and to have its own partition too.

I am hoping to eventually install three different Linux distros on the one hard drive and access my home directory and personal files from all three without any trouble. I know that they would all have to be on primary partitions. I am not sure how applications install and if they would need to be installed on each OS, or if they could accessible from all three.

Answer 1

If Linux and not Windows, I might suggest gpt partitioning. Ubuntu installs to gpt and can boot with BIOS or UEFI. But Windows only boots from gpt partitioned drive with UEFI. But with gpt partitioning you do not have any issues of primary or logical partitions.

Most desktop installs do not need separate partitions for all the various system folders. Some with SSDs may want them on rotating drive or temp files just mounted in memory.

Do not use separate /boot. Do not share /home, but create a separate /mnt/data partition. The only issue may be with different installs whether UID will be the same.

If BIOS with MBR partition, no Linux partitions have to be primary, Windows requires Primary partitions to boot. Best to use one or two primary, and then make entire rest of drive as one large extended partition for an unlimited number of logical partitions.

For the Total space you want for Ubuntu: Ubuntu's standard install is just / (root) & swap, but it is better to add another partition for /home if allocating over 30GB.: Only if gpt - all partitions in gpt are primary:

gpt: 300 MB efi FAT32 w/boot flag (for UEFI boot or future use for UEFI, you only can have one per drive, so if already existing do not attempt another)

gpt: 1 MB No Format w/bios_grub flag (for BIOS boot not required for UEFI)

for gpt(GUID) or MBR(msdos) partitioning Ubuntu partitions - smaller root only where hard drive space is limited. If total space less than about 30GB just use / not separate /home or standard install.

1. 10-25 GB Mountpoint / primary or logical beginning ext4
2. all but 2 GB Mountpoint /home or /mnt/data  logical beginning ext4
3. 2 GB Mountpoint swap logical
4. If desired leave space for added / (root) of 20GB each

Depending on how much memory you have you may not absolutely need swap but having some is still recommended. I do not hibernate (boots fast enough for me) but if hibernating then you need swap equal to RAM in GiB not GB. And if dual booting with windows a shared NTFS partition is also recommended. But you usually cannot create that as part of the install, just leave some space. Or partition in advance (recommended). One advantage of partitioning in advance is that the installer will use the swap space to speed up the install. Thanks Herman for the tip.

https://help.ubuntu.com/community/DiskSpace

suggested partitions for just Ubuntu on 3TB drive.

any problems with this partition scheme?

Another advanced suggestion from TheFu with Multiple / (root) - Post #5 similar to what I actually do

http://ubuntuforums.org/showthread.php?t=2170308