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Linux boot partitions and how to set them up

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Re: Linux boot partitions and how to set them up

#71

Post by craftkiller »

gnu8 wrote: post #59
IgorPartola wrote: post #55

Earlier quoted context omitted.

Why? One more flag to remember whereas redirection works for any program.

It doesn't matter which end of the egg.

It does when one is a standard convention compatible with all programs whereas -o does different things for different programs. For example, grep -o foo will print only the parts of the input stream that match "foo" but grep > foo will write to the file foo. Some commands don't even have a -o flag like "cat" but output redirection is still always an option.

Re: Linux boot partitions and how to set them up

#72

Post by bravetraveler »

IgorPartola wrote: post #55
yjftsjthsd-h wrote: post #23

Earlier quoted context omitted.

> grub-mkconfig > "/boot/grub/grub.cfg" Shell redirection is fine, but you could just use `grub-mkconfig -o` to set the output file.

Why? One more flag to remember whereas redirection works for any program.

Careful, not always -- if they ever work with a pager they need to be able to detect redirection

Re: Linux boot partitions and how to set them up

#73

Post by adrian_b »

CameronNemo wrote: post #19
adrian_b wrote: post #13

There are many years since I no longer create partitions on any SSD or HDD, because I believe that this serves no useful purpose and it just wastes a part of the SSD/HDD. I format directly the raw unpartitioned SSD/HDD with a file system that uses 100% of the capacity, with no wasted sectors. At least on Linux and FreeBSD, there is no need of partitions. For booting the computers, I either boot them from Ethernet or…

So your solution to not use partitions is to use multiple disks? You do understand that people invented partitions precisely because they wanted to use a single disk, right? I am glad this setup works for you, but many people will not want to need a USB drive to boot their desktop, laptop, tablet, phone, et cetera.

For a desktop, this can be transparent for the user, because it can be booted via Ethernet or from an USB drive that is attached all the time to the computer, possibly on one of the internal USB type A connectors that exist on many motherboards, precisely for this purpose.

Using a single disk with multiple partitions is less convenient than using a separate boot drive, because the separation makes easier the reuse of both the boot drives and of the root drives in other computers, or their copying onto drives of different sizes, when migrating or cloning operating systems.

For a laptop that contains encrypted SSDs/HDDs, using an USB drive to boot it, which is not normally kept with the laptop, can be used for improved security, because only in this case no secret keys need to be stored on the encrypted drive. Even if the secret keys are also encrypted, they must be encrypted with a key derived from a password, which can make their decryption much easier than the decryption of a drive encrypted with a random key.

Re: Linux boot partitions and how to set them up

#75

Post by [deleted] »

CameronNemo wrote: post #19
adrian_b wrote: post #13

There are many years since I no longer create partitions on any SSD or HDD, because I believe that this serves no useful purpose and it just wastes a part of the SSD/HDD. I format directly the raw unpartitioned SSD/HDD with a file system that uses 100% of the capacity, with no wasted sectors. At least on Linux and FreeBSD, there is no need of partitions. For booting the computers, I either boot them from Ethernet or…

So your solution to not use partitions is to use multiple disks? You do understand that people invented partitions precisely because they wanted to use a single disk, right? I am glad this setup works for you, but many people will not want to need a USB drive to boot their desktop, laptop, tablet, phone, et cetera.

[deleted]

Re: Linux boot partitions and how to set them up

#77

Post by saghm »

sagarun wrote: post #56

Meanwhile the apple firmware cannot read vFAT ESP. Apple wants ESP to be HFS.

Out of curiosity, how recent is this? I haven't owned my own macbook since the pre-touchbar era (I think the last model I had was the early 2015 Pro), and I had heard that Linux had gotten harder to boot since then due to newer firmware (I remember hearing for a time the newer models were yet to get wifi support on Linux, although I don't know how long that lasted), but at least up until then I was able to use a fairly typical Linux setup dual booted alongside MacOS. I remember using a blogpost I found as a reference, but I think the order of the steps I used were turning off FileVault, shrinking the main MacOS partition by the amount I wanted to use for Linux, doing the Linux install the way I normally do (one FAT ESP partition with refind installed, then the rest as a LUKS volume with LVM root and swap), turn off SIP by booting the macbook into recovery, booting into MacOS and running the `bless` command to set the refind partition to boot by default, rebooting back into recovery to turn SIP back on, and then finally booting back into MacOS and turning FileVault back on. Essentially, by temporarily turning off SIP and FileVault, I was able to get Linux booted by default with my usual LUKS/LVM setup but also have the option to select MacOS from my refind menu and have that booted with the usual FileVault/SIP protections. Based on what I'd read about the efforts to support Linux on the new ARM macbooks and Apple seemingly not going out of their way to block this, I would have thought that this method would still work, although maybe there's something I'm missing.

Re: Linux boot partitions and how to set them up

#78

Post by cryptonector »

yjftsjthsd-h wrote: post #31
2OEH8eoCRo0 wrote: post #9

Earlier quoted context omitted.

ZFS is the "crypto solves this" of filesystems. Adding out of tree ZFS to the boot mix sounds hella complicated.

Interestingly, GRUB actually supports ZFS; it has the dubious distinction of being the only extant implementation of ZFS that's GPL licensed, but... probably because of that... it's separate from the main OpenZFS implementation is extremely feature-poor. This results in fun things like Ubuntu's root-on-ZFS layout creating 2 pools; a boot pool (bpool) that GRUB can read, and a root pool (rpool) with the OS. It's not t…

That's because in the mid-oughts Solaris used GRUB for booting.

It's really nice because you get to boot from multiple datasets in the same pool so upgrades and downgrades can be very smooth.

Re: Linux boot partitions and how to set them up

#79

Post by cryptonector »

Volundr wrote: post #44
yjftsjthsd-h wrote: post #31

Earlier quoted context omitted.

Interestingly, GRUB actually supports ZFS; it has the dubious distinction of being the only extant implementation of ZFS that's GPL licensed, but... probably because of that... it's separate from the main OpenZFS implementation is extremely feature-poor. This results in fun things like Ubuntu's root-on-ZFS layout creating 2 pools; a boot pool (bpool) that GRUB can read, and a root pool (rpool) with the OS. It's not t…

Interesting. I've never really wanted on boot on ZFS, and I definitely don't see the point if I'd need a dedicated pool for it.

It's a lot easier to manage one pool occupying one large partition on all the disks in the pool than it is to manage any number of partitions without pooling.

Re: Linux boot partitions and how to set them up

#80

Post by blueflow »

adrian_b wrote: post #13

There are many years since I no longer create partitions on any SSD or HDD, because I believe that this serves no useful purpose and it just wastes a part of the SSD/HDD. I format directly the raw unpartitioned SSD/HDD with a file system that uses 100% of the capacity, with no wasted sectors. At least on Linux and FreeBSD, there is no need of partitions. For booting the computers, I either boot them from Ethernet or…

You can still do BIOS boot on disks without partitions. One huge advantage of "legacy" boot is that it can work filesystem-agnostic, avoiding and secondary FS implementations in the firmware or in the bootloader.

And if you go that far, you can throw out any FS kmod from the initrd except for what you need for your root partition. Including vfat.

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