[Solved] - Attempt at a multi-boot setup initial partitioning concept

Zhme · 2018-12-01 05:07:55

I have a small dose of knowledge with GNU/Linux. I started out like as most did with only the most narrow of assumptions and a hunger to know more. At first, I felt like a mechanic trying to fix a car with a toothbrush. After having installed Arch (after several days of trial and error) and gotten a few desktop environments configured, having configured wireless network access with Wpa_supplicant, and having a general knowledge of partitions and filesystems, I then felt like I was a mechanic with a car manual and a few hand tools. A few months later, a few fresh installs later, and with different configurations, I felt like I had replaced a carburetor and an ignition coil, and that my toolbox had grown to several ratchets, drivers, pliers, and a working floor jack. Once I learned how to research more effectively and utilize forums more appropriately. With all of this in my I am careful to read heavily into what I'm using before hitting the return key, but just recently I started work at a new factory which refurbishes Apple products. I have never had much experience with Macintosh but I do enjoy it's similarities with Linux OS's. Anywho, I was inspired to use my 1T HDD for more than just a small Arch distro, I was hoping to add a "Hackintosh" OS dual boot and also possibly one more Linux distro if all goes well.

I mentioned before that I have a very basic understanding of partitions and filesystems which is why I dubbed my place into it's proper home, the Newbie Corner. So let's get to the question. I have lets say 1000G of HDD that is only holding my /boot, /, and, swap partitions. I wanted to re-partition entirely and use the first /boot partition for all three boot loaders, and the very last partition which would be swap to be utilized by all 3 distro's for swap. Which I have read is a suitable way to handle such an OS configuration.

I assumed that I can use 1G of boot, in the first partition for all 3 distro's. Then have 3 distro's separated by /, /home, /, /home.... etc, and finally and swap which takes about 10% of the end of the drive and is utilized by all three.

Please be kind, but is this a correct assumption on my part?

Last edited by Zhme (2018-12-02 22:35:07)

ewaller · 2018-12-01 15:35:42

Mostly yes.

Is this an MBR or a uEFI system? 1GB seems of boot seems a bit much. Aside from that, the primary issue with your question is the concept of boot loader. You will only have one. It does not matter which distro you choose to use to manage it, but you only install one, then you configure it to allow you to pick which kernel you want to boot. You will also configure the boot loader as to any initrds that are required, and where the root file systems are located for each of the distros.

Your post was not exactly clear, but you will want separate partitions for the root for each distribution. You probably want separate home partitions for each distro as well. The issue is with configuration files stored in the $HOME. What you can do is have a common data volume that is mounted by each OS, so you can share music, video, photos, documents, etc... Source code should be treated with care because the different distros might have different libraries installed, so you may want to keep development environments separate.

Using the same swap space for multiple installations is OK, with a really major but. If you share the swap partition, DO NOT USE suspend to disk if it is configured to use the swap partition. Bad things© will happen.

Zhme · 2018-12-01 18:52:01

Sorry about my post details, I usually avoid making posts on my Friday, after a long week I usually have a drink or two. This is a uEFI system, I have my primary OS being Windows on a separate SSD which only has windows. My extra HD currently has about 512MB of boot partition and 20G of swap at the end, then entire middle is root and I have no home partition. I use rEFInd for my bootloader so I'd imagine I have to configure each distro for rEFInd to load them. I assumed I would have to wipe the whole drive and restart because I'm still very unknowledgeable about memory usage and addressing. From my limited point of view I assume that my root drive might have data in only the first (or closest to the front) part of the HD and that it could possibly be safe to delete the swap partition, resize the mount partition, add all of the various partitions after and add a swap at the end. Although, like I said i'm not sure where the memory would be located that is present with my current OS, it could be scattered about the HD in relevant locations for the filesystem to organize them. I look at a second option (keeping in mind that rEFInd currently loads my Windows OS and being unsure whether it will cause problems loading it), which otherwise has been my go to option, so as to avoid overlapping issues and novice partitioning mistakes. Which is to dd the drive and repartition from scratch for all 3 builds, and build the first OS and get Arch going with a bootloader that recognizes my Windows SSD OS, then add each alternate distro one at a time to work out the kinks.

At this point I am prepared to tackle any of the issues that I may encounter having Windows loaded by refind. I just would like to know which method is most appropriate to be safe, efficient and well thought.

Also, I had read the other day that 1G is a good size for the boot partition, I don't remember where or why they suggested that but I felt it was probable that the writer may have known more than I. I don't know what suspend to disk is, but I will shortly! Thank you for the response!

loqs · 2018-12-01 19:41:21

If the device was formatted as three partitions ABC which have three consecutive block ranges then then deleting C and shrinking B will not impact A.
How the device itself stores those locations does not matter to the OS it relies on the device to return the correct block for any address.
I would follow ewaller's suggestion

boot
archroot
archhome
otherroot
otherhome
moreroot
morehome
data
swap

Then symlink or bindmount /home/username/Documents to /data/username/Documents etc

2ManyDogs · 2018-12-01 19:56:11

I have several multi-boot machines. Each distro has one partition (boot, root, and home all on the same partition) and then I have one shared swap partition (I don't hibernate or suspend) and a separate shared data partition. I used to separate boot and home, but it's more trouble than it's worth to me.

Last edited by 2ManyDogs (2018-12-01 19:58:06)

Zhme · 2018-12-01 20:00:11

at the moment i've decided to use 200G approx. per distro, and was planning to use 50G for the root and the rest of the 150G for home files, leaving the second to last partition approx. 60G for shared data before the swap.

512MB - boot

Arch:
50G - root
150G - home

Possibly a "Hackintosh":
50G - root
150G - home

Undecided Linux:
50G - root
150G - home

60G - shared data
---
200G windows data ------ NTFS unused by any of the distros
---
final 10% approx. - shared swap

I am curious whether the placement of the partition for Windows data and swap should be related, I believe I've read that placement on the inside or the outside of the drive gives differing speeds, and I believe that swap is supposed to be the very last partition indefinitely if I am not mistaken. So does this seem like a decently formal layout for a proper multi-booted installation? I also was curious about the root size being 50G to be more than necessary, but I try to leave room for error, hopefully not too much room?

2ManyDogs · 2018-12-01 20:07:28

If you keep large collections like music and video in the shared data partition, 150G for each home is way more than I think you will need. I'd shrink those and either use the space for shared data or save some unallocated in case you decide to install something else.

Last edited by 2ManyDogs (2018-12-01 20:08:03)

Zhme · 2018-12-01 20:10:37

so the shared data partition should be treated basically like the main storage for each distros files, and the home partitions will be for user and program configurations and such? If so I don't need much more than 20G i'd imagine giving myself plenty of space. And as far as each different root partition is 50G much higher than is necessary or does that look okay for the most part?

2ManyDogs · 2018-12-01 20:16:58

Yes, you can keep everything you want available to all the distros in the shared data partition, and just use home for configs and the few things each user needs separate. 50G is more than I use for root (this machine has 11G for root, boot, and home together, and some of my machines use even less), but it depends a lot on what you plan to install. For some people 50G would not be enough. Since you have plenty of space and don't want to worry about resizing root, 50G should be fine. (ETA -- see loqs' post below).

See this topic for the wide range of root partition sizes: https://bbs.archlinux.org/viewtopic.php?id=141574

Last edited by 2ManyDogs (2018-12-01 20:20:55)

loqs · 2018-12-01 20:19:17

50G for root without a separate /var being enough depends entirely on use case.

Zhme · 2018-12-01 20:26:38

Okay well the sizing of the partitions is going to paper now so I can sate my OCD for alignment xD, although I have a final question. Since I did not mount to a /home when pacstrapping and so forth. Does making a home partition for my current Arch build require some fiddling to appropriately repath or reconfigure certain applications?

loqs · 2018-12-01 20:30:50

pacman packages never contain files for /home the filesystem package just provides the empty directory /home

Zhme · 2018-12-02 00:01:28

So there was a problem, I forgot to genfstab after repartitioning and my arch didn't boot up. So I live booted to chroot in and had issues mounting. I remade the filesystem for my root, which I didn't know I had to do again after resizing. Then when I go to chroot I get

mount point does not exist.
Failed to setup chroot /mnt

loqs · 2018-12-02 00:08:34

After shrinking a partition you need to shrink the filesystem on the partition if it supports that operation or recreate the filesystem.
After you formatted the root filesystem of the arch install and mounted it to /mnt did you run pacstrap before arch-chroot?

Zhme · 2018-12-02 22:34:37

I did not. After running pacstrap, I basically had a fresh install, which isn't horrible but I was under the assumption that my current OS after being resized would still be intact. Arch is now working again and almost back to the way it was. Marking solved.

loqs · 2018-12-02 23:20:08

Parted#Resizing_partitions covers resizing a partition leaving the filesystem intact. (a backup is still recomended)

Arch Linux

#1 2018-12-01 05:07:55

[Solved] - Attempt at a multi-boot setup initial partitioning concept

#2 2018-12-01 15:35:42

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#3 2018-12-01 18:52:01

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#4 2018-12-01 19:41:21

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#5 2018-12-01 19:56:11

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#6 2018-12-01 20:00:11

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#7 2018-12-01 20:07:28

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#8 2018-12-01 20:10:37

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#9 2018-12-01 20:16:58

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#10 2018-12-01 20:19:17

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#11 2018-12-01 20:26:38

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#12 2018-12-01 20:30:50

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#13 2018-12-02 00:01:28

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#14 2018-12-02 00:08:34

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#15 2018-12-02 22:34:37

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

#16 2018-12-02 23:20:08

Re: [Solved] - Attempt at a multi-boot setup initial partitioning concept

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