[SOLVED] Partioning advice dualboot LM18.3 and 19

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MyM
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[SOLVED] Partioning advice dualboot LM18.3 and 19

Post by MyM » Mon Oct 15, 2018 1:33 pm

Hi all,
I'd like to install LM19 along side the current LM18.3 and would like a little advice on partitioning. Currently the situation is as follows with some /home folders sym-linked to directories on the HDD.

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donner@donner-desktop ~ $  df -h --output=source,fstype,size,used,avail,pcent,target -x tmpfs -x devtmpfs
Filesystem     Type  Size  Used Avail Use% Mounted on
/dev/sda1      ext4   39G  8.4G   28G  23% /
/dev/sda2      ext4   21G  774M   19G   4% /home
/dev/sdb3      ext4  800G   71G  689G  10% /media/DATA
donner@donner-desktop ~ $ 

The 64GB SSD is dedicated to "/" and /home with select directories (Downloads, Documents, Music, Videos, Pictures) sym-linked to the 1TB HDD.
I am thinking the way forward is to resize sda1 and sda2 to half their current size; move sda2 next to sda1, then use the free space to add another two partitions ("/" and /home)for LM19, which, I believe need to be logical partitions.
I've run a live session of LM19 and all is well on the hardware front. I'd like to take a better look at it before committing and eventually swapping LM18 for some other distro.
If my partitioning plan is feasible, I would like to point LM19 to the current LM 18 sym-linked directories, thus leaving any config preferences in the respective /home directories of each distro. Does this look reasonable?
cheers,
Last edited by MyM on Mon Oct 22, 2018 9:23 pm, edited 1 time in total.

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Re: Partioning advice dualboot LM18.3 and 19

Post by WharfRat » Mon Oct 15, 2018 2:29 pm

MyM,

What you're attempting sounds feasible.

Resize/move and create your partitions from the live session and make sure you can boot 18 before installing 19.

You will only need one logical partition for home as that would be your 4th primary.

Good luck :wink:
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Re: Partioning advice dualboot LM18.3 and 19

Post by rene » Mon Oct 15, 2018 2:35 pm

MyM wrote:
Mon Oct 15, 2018 1:33 pm
[ ... ] I would like to point LM19 to the current LM 18 sym-linked directories, thus leaving any config preferences in the respective /home directories of each distro.
Especially given that part I would recommend not separating out /home from / for either distribution; to have a total of just two partitions on /dev/sda, one for Mint 18 and one for Mint 19. Well, or three, adding a swap partition shared between them but it's not clear if you have a swap partition now and/or whether it's on the HDD.

That is, I would as root (or from the live system) copy your current /dev/sda2:* to /dev/sda1:/home/ and comment out the /home entry in /dev/sda1:/etc/fstab. Depending on level of OCD, then either shrink /dev/sda1 to half the SSD and delete/recreate /dev/sda2 to fill the other half, or just leave them be so that Mint 18 has its current 40G and Mint 19 gets the other 20G; the former home partition.

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Re: Partioning advice dualboot LM18.3 and 19

Post by MyM » Tue Oct 16, 2018 12:15 am

Great. There is another issue of concern with my plan, and, as I'm new to Linux, I'm wondering how things might play out:
My intention is to format the "new" partition as GUID (GPT) with the idea of using Refind --at a later date-- for the boot manager. However, as the current partitions were formatted as MBR (msdos), I'm uncertain how that will impact the systems as a whole. Assuming, there are no hardware compatibility problems with LM19, and I like it well enough to ditch 18.3, I'll then reformat that partition to GPT and try out another distro.
WharfRat wrote:
Mon Oct 15, 2018 2:29 pm
...
You will only need one logical partition for home as that would be your 4th primary.

Good luck :wink:
If I'm not mistaken, even that could be a primary partition, except that I'd then have to to shrink one of those primary partitions if ever I needed add another, which would then have to a logical partition. Admittedly, I'm not well-versed in advantages to partitioning one way or the other. Since the SSD is so small (and old), there is not much point in trying to use it for more than one "mainstay" distro and another "test" distro. The two separated /home partitions, also on the SSD and each belonging to their respective versions, are only to preserve tweaks. They should both, however, be able to access the sym-linked directories (Download, Documents, Pictures, Videos, Music) residing on the HDD. Which is where the /swap is located as well. Incidentally, I'm assuming I can use the same /swap for both distros. Please correct me if I'm wrong.

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Re: Partioning advice dualboot LM18.3 and 19

Post by MyM » Tue Oct 16, 2018 12:29 am

rene wrote:
Mon Oct 15, 2018 2:35 pm
MyM wrote:
Mon Oct 15, 2018 1:33 pm
[ ... ] I would like to point LM19 to the current LM 18 sym-linked directories, thus leaving any config preferences in the respective /home directories of each distro.
Especially given that part I would recommend not separating out /home from / for either distribution; to have a total of just two partitions on /dev/sda, one for Mint 18 and one for Mint 19. Well, or three, adding a swap partition shared between them but it's not clear if you have a swap partition now and/or whether it's on the HDD.

That is, I would as root (or from the live system) copy your current /dev/sda2:* to /dev/sda1:/home/ and comment out the /home entry in /dev/sda1:/etc/fstab. Depending on level of OCD, then either shrink /dev/sda1 to half the SSD and delete/recreate /dev/sda2 to fill the other half, or just leave them be so that Mint 18 has its current 40G and Mint 19 gets the other 20G; the former home partition.
Thank you for your input, Rene. I don't understand Linux well enough to predict what complications may arise. My reasoning for separating the "/" and "/home" was to avoid loss of preferences and data should I be forced to reinstall. Your suggestion re: copying /dev/sda2 to a /home directory on sda1 sounds a little more complicated (to me, at least) then simply using Gparted to shrink, move, and reformat free space. Is there any reason / cautionary advice that I should avoid my intended approach? BTW, sorry for not making it clear: the /swap partition is, indeed, on the HDD.

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Re: Partioning advice dualboot LM18.3 and 19

Post by WharfRat » Tue Oct 16, 2018 12:36 am

Just to clarify the partitioning, the 4th would be the extended partition where you would then setup the logical partitions.

I sort of misspoke in my first post.

Also you can't mix gpt and msdos partitions on a disk. The disk is either gpt or msdos partitioned.

And yes you can use the same /swap for both distros.
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Re: Partioning advice dualboot LM18.3 and 19

Post by rene » Tue Oct 16, 2018 9:54 am

MyM wrote:
Tue Oct 16, 2018 12:29 am
Is there any reason / cautionary advice that I should avoid my intended approach?
A little no, a bit yes. The thing is that I noticed you having less than 1G in use on your home partition; that the other 19G or so were basically "wasting away". Now, with 40G for / as currently that's not much of an issue: 40G is generally quite enough for most uses. Now that you are however planning on halving / and /home, leaving / with "only" 20G that changes a bit; it's not hard to fill up that 20G if you don't proactively clean up the, say, apt cache. Halved current / and halved current /home together gets you 30G, which minus the less than 1G in use leaves you with what I would feel better breathing room.

Together with the fact you have your most definitively non-volatile data on the HDD anyway already this sparks the recommendation; it's the general issue with separating out partitions for specific uses: fragmentation of free space. I'm also from a generation/persuasion in which shrinking and/or moving partitions around would be the hard option instead -- but sure, I guess that parted makes that easy enough that you could find the latter easier.

Still, just in case you would in fact like to do the merging of / and /home let me walk you through it; it's pretty simple. I would suggest doing this from a live DVD/USB lest you run into issues with e.g dbus keeping /home busy. You'd open a terminal from the live system and become root with sudo -i. Create mountpoints for your current / and /home partitions with mkdir /mnt/{tmp,home} and mount them with

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# mount /dev/sda1 /mnt/tmp
# mount /dev/sda2 /mnt/home
Verify with ls -l /mnt/tmp and ls -l /mnt/home (or the graphical file manager if you insist) that your / and /home are now available from /mnt/tmp and /mnt/home respectively, and simply copy over your /home to /:

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# cp -av /mnt/home/* /mnt/tmp/home/
This should verbosely copy over your home directory/ies (probably also a current "/home/lost+found" directory; you can after the copy finished just delete that manually with rmdir /mnt/tmp/home/lost+found).

Verify again that /mnt/tmp/home/ now contains your home directory/ies and comment out the /home entry in /mnt/tmp/etc/fstab. Preferably with e.g. nano /mnt/tmp/etc/fstab if you're comfortable enough with the nano console editor but (still as root) xed /mnt/tmp/etc/fstab will also work. Commenting out an entry means placing a "#" at the beginning of the line.

You are done at this point: can reboot the system from the SSD again and should find yourself in your normal environment, although with a /home directory that's now on /dev/sda1 directly. Note that it's also still on /dev/sda2; that nothing's irreversible and that this should as such be safe to try.

If all checks out you may now feel free to resize /dev/sda1, delete /dev/sda2 and recreate it as the Mint 19 target partition; you'd want to use the "Something else" option while installing latter so as to set /dev/sda2 as your target / and format it. Or to not resize and give Mint 19 the 20G former /home partition.

Or to not do any of it and use your own envisioned setup after all. As said, fragmentation of free space may become a bit of an issue at some point, but it'll work...

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Re: Partioning advice dualboot LM18.3 and 19

Post by rene » Tue Oct 16, 2018 12:28 pm

Noticing while rereading: the above is by the way while assuming you don't have home encryption enabled. If you do, it's not much else, but I do believe /mnt/tmp/home/* would in that case miss an important dot-directory in /home. I'd have to check if you do have home encryption enabled, but if not, the above is fine.

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Re: Partioning advice dualboot LM18.3 and 19

Post by MyM » Fri Oct 19, 2018 10:40 am

rene wrote:
Tue Oct 16, 2018 12:28 pm
Noticing while rereading: the above is by the way while assuming you don't have home encryption enabled. If you do, it's not much else, but I do believe /mnt/tmp/home/* would in that case miss an important dot-directory in /home. I'd have to check if you do have home encryption enabled, but if not, the above is fine.
Thank you very much Rene for taking the time to "walk me through" the steps needed to take your approach. There is no encryption of the /home directory, so there should not be any problem in that regard.

I understand your concern re: fragmentation of free space. However, if the current sda2 /home directory is copied to the sda1 partition, would that not be overwritten if I had to reinstall 18.3? I am under the impression the whole reason to keep root and /home in different partitions is to avoid losing data and configuration tweaks. That said, since the directories containing data I want to avoid losing is already physically separated, maybe the trade-off is not such a big deal.

When LM offers to automatically install next to an existing OS, does it simply allocate the existing free space for itself? And in that case, I assume there is no possibility to establish a separate /home partition.

When I get a chance, I'll take a stab at moving ahead with this in one way or another. Two partitions or four, either way, Sylvia and Tara will just have to learn to live with each other on a 64 G ssd. They can each have their own /home ... or not.

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Re: Partioning advice dualboot LM18.3 and 19

Post by rene » Fri Oct 19, 2018 5:27 pm

MyM wrote:
Fri Oct 19, 2018 10:40 am
However, if the current sda2 /home directory is copied to the sda1 partition, would that not be overwritten if I had to reinstall 18.3? I am under the impression the whole reason to keep root and /home in different partitions is to avoid losing data and configuration tweaks.
First sentence, yes, and second, "data" yes, but you indicated having some of that separated out to HDD already anyway. "Configuration tweaks" in theory, but is that in fact more than theory for you? I.e., have you in fact tweaked (user-) configuration to a level such that 5 minutes of rummaging 'round Menu -> Preferences would not be enough to recreate the current user configuration?

Mind you, "yes" would appear to be a valid answer and certainly on systems with more than one active user but for me it's "no". Definitely I have files and directories, dot- and otherwise, in my home that I preserve across reinstalls but have like you separated out a big chunk of that to a different drive/partition anyway -- and /etc is moreover configuration-wise much more important to me than any per-user configuration. Both /etc and my home I backup regularly and certainly right before reinstalls; for me the point of a reinstall tends to be to get rid of outdated configuration and/or other accumulated junk and I as such only selectively and manually restore files from backup to the new system.

I suppose it should be noted though that I probably have not for the last 15 years or so felt the need or desire the reinstall the same version of a distribution from scratch; that my reinstalls very much are newer and/or different versions, for which that kind of selective cleanliness is more to the point. Still, merely being less selective regards restoration would be my method even if otherwise: if nothing else this would with lesser chance recreate the exact same problem on the new system as was the reason for the reinstall in the first place.

That is, certainly since splitting off my most decidedly non-volatile data in home to a different drive/partition only linked from home I do not in fact find there to be value in separating out /home from /. Find that what's left, with a few exceptions under the selective restoration from backup clause, to be of the good riddance type. I suppose your mileage may vary but would suggest some quick reflection on whether or not it actually does or only theoretically.

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Re: Partioning advice dualboot LM18.3 and 19

Post by slipstick » Fri Oct 19, 2018 7:24 pm

Here's how I have my system set up. I haven't yet installed LM19, but plan to use this method by overwriting the current (unused) LM17.3 installation. It may be more elaborate than you want to try, and the partitioning is easier if your disk is gpt. This worked very well for me transitioning from LM17.3 to LM18.3.

The following are snips from posts in different threads:

[Thread 1]
I have / and /home for each OS (currently 17.3 and 18.3) with a Data partition mounted to a Data mount point in my home directory in both systems and using the same user name in both systems. Directories such as Documents, Pictures, etc. in each of the systems home are symlinked to the same Document, Pictures,... folder in the Data partition. So whichever one I am booted into, access to my personal data is identical - I can click on Documents, Pictures, etc., or if the data I want is not in one of those folders, I click on the Data folder in home and can see all the other files and folders (including the Documents, Pictures, etc. folders). And I repeat - it looks exactly the same for either system. Files in the home folder of each system which are not personal data, such as configuration files can be different between the two systems - a good thing if you have different versions of your applications in the two systems which may require different config files. But if you are booted into one system and want to copy some data from the other home folder, you can mount it from the left pane in Nemo, click on it, go to double pane mode, then in the right pane, select the home folder of the system your are currently booted into and copy the file.

[Thread 2]
I have a triple boot system (UEFI, gpt) on a single 1TB HDD with W7 (used once a year to do my income tax return), LM17.3 (retired) and LM18.3. The way I have this set up may be a little too advanced for a complete newbie, but is really pretty simple and should be easy for a near beginner to implement if he has a gpt HDD with plenty of space on it.

What I have started doing is to have separate partitions for odd numbered and even numbered Mint editions. Actually I have a separate / and /home for each version (probably don't really need the separate /home, but I started out with that and see no reason to change at this point). I have a separate Data partition shared between both versions and have moved my thunderbird and firefox profiles onto the data partition (symlinked from the thunderbird and firefox directories in both versions) so that all my personal data, emails, and FF bookmarks are available from either version. So when I get ready to install LM19, it will replace LM17.3, but I can continue using LM18.3 while I configure LM19 at my leisure. Then I will continue upgrading to 19.1, 19.2, 19.3 in place, then LM20 will replace LM18.3. I am not using a shared /home for both because I have heard that sometimes using old versions of configuration files can conflict with newer versions of the same software, so a clean install seems safer. I made a detailed itemized list of everything I did when I moved from 17.3 to 18.3, so I think setting up 19 "from scratch" should not be too bad. I can boot into 18.3 when I want to use the computer, or boot into 19 when I have some spare time to get it configured, without worrying that I will mess something up on my working 18.3. When I get 19 configured and switch over to using it full time, I will still have 18.3 as a backup. The only complication I have run into is with "firejail" - because I moved my thunderbird and firefox profiles onto my data partition I had to add a whitelist statement for these folders in /etc/firejail/firefox.profile and /etc/firejail/thunderbird.profile.
EDIT: Per recommendation from Fred Barclay, it is best not to modify those two firejail ".profile" files, but rather to create two new files, /etc/firejail/firefox.local and /etc/firejail/thunderbird.local and put the required whitelist statement in each file, so that an update to firejail which replaces /etc/firejail/firefox.profile and /etc/firejail/thunderbird.profile will not wipe out the whitelist statements.

Here's my disk layout:

Code: Select all

Model: ATA ST1000DM003-1ER1 (scsi)
Disk /dev/sda: 1000GB
Sector size (logical/physical): 512B/4096B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system     Name                          Flags
 1      1049kB  106MB   105MB   fat32           EFI system partition          boot, esp
 2      106MB   240MB   134MB                   Microsoft reserved partition  msftres
 3      240MB   302GB   301GB   ntfs            Basic data partition          msftdata
11      322GB   344GB   21.5GB  ext4            LM18_root
12      354GB   365GB   10.7GB  ext4            LM18_home
13      387GB   483GB   96.6GB  ext4            LM18_timeshift
 4      500GB   500GB   105MB   fat32                                         msftdata
 5      500GB   522GB   21.5GB  ext4            LM17_root
 6      522GB   543GB   21.5GB  ext4            LM17_home
 7      543GB   651GB   107GB   ext4            Data
 8      651GB   668GB   17.2GB  linux-swap(v1)  Swap
10      878GB   983GB   105GB   ext4            LM17_timeshift
 9      983GB   1000GB  17.2GB  fat32           Share                         msftdata

(Quoted from another member)
"Question, how did you do that for Firefox? On Windows, I use Firefox Portable and I need to find how to do something similar on Linux. I already have the separate shared data partition (subvolume really) and I think I'll only be symlinking targeted directories in /home (e.g. Documents, Downloads, Music, Pictures, Videos, etc). As you noted, I'm also trying not to mix up incompatible configuration files between different distros hence the separate /home for each. "

(My reply)
On my Data partition, I made a new hidden (not really necessary to make it hidden) directory for the FF profile, and one for the Thunderbird profile, named .firefox and .thunderbird. Then I moved the entire Firefox profile directory named mwad0hks.default (with all its subdirectories) from its original location /home/<my user name>/.mozilla/firefox to /home/<my user name>/Data/.firefox and replaced it with a symlink mwad0hks.default in the original location pointing to /home/<my user name>/Data/.firefox/mwad0hks.default. I did the same with Thunderbird, replacing the TB profile (named zsw2x4o8.default on my system) in /home/<my user name>/.thunderbird with a symlink of the same name pointing to /home/<my user name>/Data/.thunderbird/zsw2x4o8.default . I could have skipped the intermediate .firefox and .thunderbird directories in the Data directory, but I put those in just so I would know which of those oddly named profiles were which.

Then, to make it work with firejail, I had to add a whitelist statement to /etc/firejail/firefox.profile: whitelist ${HOME}/Data/.firefox
and another to /etc/firejail/thunderbird.profile: whitelist ${HOME}/Data/.thunderbird
EDIT: Per recommendation from Fred Barclay, it is best not to modify those two firejail ".profile" files, but rather to create two new files, /etc/firejail/firefox.local and /etc/firejail/thunderbird.local and put the required whitelist statement in each file, so that an update to firejail which replaces /etc/firejail/firefox.profile and /etc/firejail/thunderbird.profile will not wipe out the whitelist statements.

Note - the names of your FF and TB profile directories may differ from mine, but should be the same format xxxxxxxx.default.
Last edited by slipstick on Fri Oct 19, 2018 10:03 pm, edited 1 time in total.
In theory, theory and practice are the same. In practice, they ain't.

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Re: Partioning advice dualboot LM18.3 and 19

Post by rene » Fri Oct 19, 2018 7:42 pm

MyM wrote:
Fri Oct 19, 2018 10:40 am
When LM offers to automatically install next to an existing OS, does it simply allocate the existing free space for itself? And in that case, I assume there is no possibility to establish a separate /home partition.
Sorry, missed a query. Yes, and no indeed. Furthermore, I do believe that even the automatic install would not create an additional swap partition, would reuse the one on the HDD, but am not completely certain: on non-VM installs, I pick the "something else" option always; tend to create all partitions in advance using for me more comfortable tools.

In any case, yes, you'll want the "Something else" option.

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Re: Partioning advice dualboot LM18.3 and 19

Post by MyM » Sun Oct 21, 2018 6:35 am

rene wrote:
Fri Oct 19, 2018 5:27 pm

First sentence,...

Mind you, "yes" would appear to be a valid answer and certainly on systems with more than one active user but for me it's "no". Definitely I have files and directories, dot- and otherwise, in my home that I preserve across reinstalls but have like you separated out a big chunk of that to a different drive/partition anyway -- and /etc is moreover configuration-wise much more important to me than any per-user configuration. Both /etc and my home I backup regularly and certainly right before reinstalls; for me the point of a reinstall tends to be to get rid of outdated configuration and/or other accumulated junk and I as such only selectively and manually restore files from backup to the new system.

That is, certainly since splitting off my most decidedly non-volatile data in home to a different drive/partition only linked from home I do not in fact find there to be value in separating out /home from /. Find that what's left, with a few exceptions under the selective restoration from backup clause, to be of the good riddance type. I suppose your mileage may vary but would suggest some quick reflection on whether or not it actually does or only theoretically.
Good point, Rene, and definitely something to take into account when I'm ready to proceed. Not one for messing around all that much with what is presented by default, I don't think there's much reason to separate a /home partition, after all. With non-volatile data preserved else where, yeah, what's the point? That said, what is it about /etc "configuration-wise" that warrants backing up and copying back after a reinstall? Application preferences, would seem the logical answer, but possibly something else?

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Re: Partioning advice dualboot LM18.3 and 19

Post by MyM » Sun Oct 21, 2018 7:03 am

slipstick wrote:
Fri Oct 19, 2018 7:24 pm
Here's how I have my system set up.

Note - the names of your FF and TB profile directories may differ from mine, but should be the same format xxxxxxxx.default.
Thank you Slipstick for jumping in, providing a detailed explanation, and for covering a scenario I hadn't even considered (FF profile).

And now Firejail, great, even more fun "stuff" to look into. So many interesting avenues to explore and not enough time.

Speaking of which, that's it for me ... cheers, gotta run.

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Re: Partioning advice dualboot LM18.3 and 19

Post by rene » Sun Oct 21, 2018 3:11 pm

MyM wrote:
Sun Oct 21, 2018 6:35 am
That said, what is it about /etc "configuration-wise" that warrants backing up and copying back after a reinstall?
Selectively restore files from it, not copying back outright. But /etc is the system configuration directory. Something like /etc/hosts is a for me for example heavily custom file describing a fairly extensive LAN. /etc/fstab, other personal system tweaks, ...

If you configure less or even little directly in /etc then certainly feel free to care less about it.

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Re: Partioning advice dualboot LM18.3 and 19

Post by MyM » Mon Oct 22, 2018 9:19 pm

Right, well, thanks to all for the informed advice. I'll refer back to this when the time comes. At present, after noting the many difficulties people are experiencing with LM19, I'm now of the mind to wait for 19.1.

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Re: [SOLVED] Partioning advice dualboot LM18.3 and 19

Post by pgmer6809 » Tue Oct 23, 2018 1:44 am

GPT vs MSDOS disks.
For a Linux only machine I heartily recommend a GPT disk; Linux and GRUB have no issues with GPT. you can treat them the same as MBR/msdos disks, only you are not limited to 4 primary partitions. you can have I think 128.
(Windows will not let you use GPT disks without UEFI boot; Linux will let you use GPT disks with BIOS or UEFI boot.)

Having said that I must warn you that I do not think it is possible to "Convert" an msdos disk to a GPT disk.
In your OP you mentioned a GPT partition (as if that could exist on an msdos disk). GPT refers to the whole drive, not to only one partition.
When I ask GPARTED to create a GPT partition table at the start of the disk, it always warns me that this will completely erase all data on the disk.

I have never tested that warning. There may be tools that can convert msdos to GPT but I don't know of them.
So if you are planning to convert to GPT you definitely should backup all your current partitions (with the dd cmd most likely) to your HDD, reformat the SSD as GPT, create your new OS and Home and BIOSGRUB partitions, then restore those partitions that you want again using the dd command..

If/When you do create the GPT disk, you should create another partiion with the type "biosgrub", it does not have to be very big -- it only needs to hold the early grub code; a few MB should do it.
in an MSDOS disk, grub has to store the code that would go here, in some 'hidden' or 'hopefully unused'' tracks / cylinders. This is somewhat fragile as there is no way of ensuring that some other program (e.g. a DRM'd windows program) does not attempt to use this space and overwrite grub. In a GPT disk this workaround is not necessary so GRUB can have its own partition to store the code it needs to run to get the kernel loaded.
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Re: [SOLVED] Partioning advice dualboot LM18.3 and 19

Post by rene » Wed Oct 24, 2018 5:08 am

pgmer6809 wrote:
Tue Oct 23, 2018 1:44 am
(Windows will not let you use GPT disks without UEFI boot; Linux will let you use GPT disks with BIOS or UEFI boot.)
Slight adjustment: Windows can not boot from a GPT-partitioned disk on BIOS-system. Having it, say, boot from a small partition on an MBR-partitioned disk with Windows itself and/or its data partitions on a GPT-partitioned disk is fine.

The standard gdisk partitioning tool can convert between MBR and GPT; see the "r", recovery and transformation options, submenu of the "x", extra functionality (experts only), menu.

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