Which dual-boot partitioning choice (of 3) might be preferred?
 

I am a beginner and have read a lot to date ... but not yet done it. ;-)

I have a laptop (BIOS) with three Windows partitions: Win7 / Data-NTFS / small Fat32. Space is available for Linux.

:::

I plan a (Linux) Data Partition to share docs between Linux distros. I would like freedom to add one additional Linux distro in near future.

Per above, I already have an NTFS Windows partition but that's mostly for Windows purposes. I know know I can -- and intend to -- cherry-pick (read) files from the NTFS partition but don't plan to write to it much from the Linux side.

:::

I understand (as a newbie) it is best not to let two distros share a common /home. But I also have heard that when you have a separate data partition it's good to keep /home under root (/).

I would love some insight, experience, advice, recommendation on any of this, *especially* as to which of the partition plans below might be best.

Currently thinking that "B" is a slight win over "C" but your guidance is most welcomed!

[Also does placing SWAP ... then the Data Partition ... followed by the distros appear an optimal sequence? As long as sizing of SWAP and Data Partition is done well, with no future changes expected, it sounds right to me to put them in that order before the distros.]

Thanks in advance for the help. My pro/con thoughts are bulleted.

:::

For Linux Side of Windows7-Linux Dual-Boot:

A. Workable but *least* favorite choice:

Partition 1: SWAP (shareable)
Partition 2: DATA PARTITION

Partition 3: DistroA
Partition 4: /home for DistroA (i.e., separate home)

Partition 5: DistroB
Partition 6: /home for DistroB (i.e., separate home)

• Follows recommendations to have separate HOME partitions
• Allows for easy reinstalls
• Results in unwieldy number of total partitions [Win+Linux]

=============================

B. Possible option - (no separate /home[s])

Partition 1: SWAP (shareable)
Partition 2: DATA PARTITION

Partition 3: DistroA with /home internally held
Partition 4: DistroB with /home internally held

• Elegant because fewer partitions
• [Con:] Makes more work at time of reinstall

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C. Central /home with sub-home-directories for each distro --> Thoughts?

Partition 1: SWAP
Partition 2: DATA PARTITION

Partition 3: DistroA
Partition 4: DistroB

Partition 5: /home:

/home/[distroA]/[username]
/home/[distroB]/[username]

• Keeps one separate HOME partition (easy reinstalls)
• Fewer partitions; keeps Linux partitions to five.
• [Con:] Complexifies HOME partition configuration.

=============================

Personally I would go three partitions, 1 for your Win 7 os install, 1 for your preferred Linux OS and one as a data partition formatted with NTFS. Then use vmware player or workstation if you want to play with a bunch of other distros.

What benefit does having a triple boot os give you? None that I can think of.

Many application packages create configuration files as hidden files in the /home/user directory. If /home is shared between two distributions then you could run into problems with your application configuration files when the two distributions install different releases of an application program.

There can be another major problem with 2 distributions sharing /home. A distribution assigns a unique number for each user name. In the file metadata ownership is kept by user number, not by user name. If two distributions assign different user numbers to a user name then your user's file system will be inaccessible to the user in the second distribution installed. This can be overcome when you install the second distribution by immediately deleting the user and then add the user again and specifying that the user in the second distribution is assigned the same user number as they were given in the first distribution.

You would also have the same problem with your shared data partition in options A and B if the file system supports permissions If you use a Windows file system for the data partition then the problem is moot because Windows does not have permissions. Even so, I recommend that you use a Linux file system for the shared data between your Linux systems.

If your two Linux distributions are the same (for example I have one Debian wheezy and two Debian jessie installations) then you will have no user number problems if you create the users in the same order in each installation.

The only effect of the order of the partitions is the speed at which your system will run. Place the busiest partition in the middle of the drive and the least used partitions at the front and back. swap will be your least used partition.

--------------------
Steve Stites

I never really saw the point of having a multi-boot system between multiple Linux distros. A dual-boot with Windows and Linux, sure, but not multiple Linux, there's just no real point. As Kustom42 said, pick a solid distro for your dual-boot with Windows, and then if you want to experiment (or if you need one particular distro in order to do one particular job) do it with VMs.

I've never seen a Linux distro that didn't let you specify the UID/GID when creating the user. Sometimes it's under some kind of "advanced" menu, but it's always there, at least with the distros I use. So he could either pick a UID/GID first and specify it for both installations, or just make a note of what it is on the first installation and specify it on the second. It shouldn't be any more complicated than that, and he certainly would not need to create a user, delete it, and then create it again with a different UID...if nothing else he could always just change the UID associated with a user name on-the-fly.

Have you checked the partition types, before attempting install?
Anyway wins has 3 partitions, we know that atleast 2 are primary paritions, the other 1 maybe a primary or Extended partition.
Is it a dynamic disk?
2 have ntfs file systems, 1 of them maybe the recovery partition.
This is some of the info that we need to really assist you.

Follow-up in response to input and assistance above is coming; this is place holder, thanks - Linux4mQuest

Follow-up 1
 

The general direction of comments seems to advise *not* to bother adding an additional (i.e., second) Linux distribution to a Win-Linux dual-boot ... and to use VM method if ever needed. I am quite persuadable.

[However, VM is another big topic I have not yet studied. It brings up questions like possibility of saving files ("persistence"?), etc....or is the purpose of VM-ing just for quick one-time "take it for a spin" views of distros?]

Maybe the core of my question was whether the following /home partition configuration is worth trying when you have two Linux installs in Win-Linux dual-boot:

I think Steve's (jailbait's) response might have missed second & third quoted lines, saying :

Don't the subdirectories above avoid mixing/sharing of /home (and its configuration files, etc.) since /home is broken out into distro subdirectories?

Thanks also to Steve for reminders on User ID numbers and usernames.

:::

I might be now recovering from a spate of newbie-info-overload with all the partitioning possibilities with its concommitant risk of over-complex-ifying things.

I might just fall back to option B listed in my original question in order to retain the option for a second Linux install. It might also be a cleaner configuration from which to delete any second Linux installation.

This response is sketchier than wished but have to run...

VMs are full systems that run inside a little "pretend" computer managed by the VM host. By full systems, I mean full. You can do everything you could possibly want to do on a real machine in a VM instead with just a few limitations:
1) It will run slightly slower, though with virtualization built into modern processors, the difference is small
2) It will not have the graphics capabilities of running on bare metal, this is really only an issue with demanding games though
3) Your system must have enough resources to support both the host OS and the guest OS at the same time (namely RAM)
4) Direct hardware access can be finicky (interfacing the VM with some USB peripheral, for example)

Yes it will have persistence, it even has its own "hard drive" which it partitions and manages itself like it's the real thing (in reality it's just a regular file on your host machine).

I have a Windows 7 VM on my work machine that has been running 24/7 for the last ~4 years (other than the occasional reboot). It's where I do all of my Windows-specific work (Microsoft Office, Acrobat, and other Windows-only tools).

You can treat VMs like real systems. You can run a Linux VM on a Windows host, a Linux VM on a Linux host, a Windows VM on a Linux host, etc. Any combination you want. You just tell the VM manager how many processors, how much RAM, and what size drive to allocate for the VM, then fire it up, install its OS, and then it's like a mini-machine inside your real machine.