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I'm attempting a btrfs install now.

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Jimmy Johnson

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Aug 5, 2021, 3:55:12 PM8/5/21
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The btrfs file system is made. The slackware dvd iso is dated 8/5/21, I
wrote it to a flash drive and I'm in the installer now. It's installing
now, I see no changes in the installer, it did identify my btrfs
partition where I'm doing the install. So far it's looking good, I'll
keep you updated.
--
Jimmy Johnson

Slackware64 Current - i7-2820QM - EXT4 at sda9
Registered Linux User #380263

John McCue

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Aug 5, 2021, 4:52:56 PM8/5/21
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Jimmy Johnson <field.e...@gmail.com> wrote:
> The btrfs file system is made. The slackware dvd iso is dated 8/5/21, I
> wrote it to a flash drive and I'm in the installer now. It's installing
> now, I see no changes in the installer, it did identify my btrfs
> partition where I'm doing the install. So far it's looking good, I'll
> keep you updated.

So on Current ? Will look forward to your posts.

Jimmy Johnson

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Aug 5, 2021, 5:19:52 PM8/5/21
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On 8/5/21 12:54 PM, Jimmy Johnson wrote:

> The btrfs file system is made. The slackware dvd iso is dated 8/5/21, I
> wrote it to a flash drive and I'm in the installer now. It's installing
> now, I see no changes in the installer, it did identify my btrfs
> partition where I'm doing the install. So far it's looking good, I'll
> keep you updated.

It's looking like I can't do this.
My grub is using a older kernel and can't mount btrfs. I don't know if I
can update the kernel on sda1 and the slack btrfs install is on sda7,
any advise or help?

Jimmy Johnson

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Aug 5, 2021, 6:06:44 PM8/5/21
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On 8/5/21 2:19 PM, Jimmy Johnson wrote:
> On 8/5/21 12:54 PM, Jimmy Johnson wrote:
>
>> The btrfs file system is made. The slackware dvd iso is dated 8/5/21,
>> I wrote it to a flash drive and I'm in the installer now. It's
>> installing now, I see no changes in the installer, it did identify my
>> btrfs partition where I'm doing the install. So far it's looking good,
>> I'll keep you updated.
>
> It's looking like I can't do this.
> My grub is using a older kernel and can't mount btrfs. I don't know if I
> can update the kernel on sda1 and the slack btrfs install is on sda7,
> any advise or help?

I can't convert back to ext4 without doing a new install.

But I can do a new grub install and then install btrfs tools to the new
grub install.

But I won't do anything now because my head hurts and needs a rest.
--
Jimmy Johnson

Slackware64 Current - AMD A8-7600 - EXT4 at sda6
Registered Linux User #380263

John McCue

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Aug 5, 2021, 6:44:08 PM8/5/21
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Jimmy Johnson <field.e...@gmail.com> wrote:
> On 8/5/21 12:54 PM, Jimmy Johnson wrote:
>
<snip>
>
> It's looking like I can't do this.
Good try anyway

> My grub is using a older kernel and can't mount btrfs. I don't know if I
> can update the kernel on sda1 and the slack btrfs install is on sda7,
> any advise or help?

I could be wrong, but I think you cannot had /boot and
maybe / as btrfs.

Jimmy Johnson

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Aug 5, 2021, 6:55:58 PM8/5/21
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Yes, current. I've been using ext4 for what seems like forever and never
thought about my grub install needing btrfs-tools to read btrfs /boot.
Reinstalling grubs a little scary because I have 12 linux systems on
this computer that rely on the grub install. But I won't back down. :)
--
Jimmy Johnson

Jimmy Johnson

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Aug 5, 2021, 7:02:02 PM8/5/21
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On 8/5/21 3:44 PM, John McCue wrote:

> I could be wrong, but I think you cannot had /boot and
> maybe / as btrfs.

The install is all on one partition, I won't change that. I've never
used separate partitions.
--
Jimmy Johnson

Auric__

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Aug 5, 2021, 11:28:24 PM8/5/21
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Jimmy Johnson wrote:

> On 8/5/21 3:44 PM, John McCue wrote:
>
>> I could be wrong, but I think you cannot had /boot and
>> maybe / as btrfs.
>
> The install is all on one partition, I won't change that. I've never
> used separate partitions.

I've had /boot on a separate partition since... I'm gonna say maybe since
ext3 was released? I was running multiple distros on a single machine, so it
made sense to me. I've also always had it set to not automount.

--
Entropy and optimism: the twin forces that make the universe go around.

Jimmy Johnson

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Aug 6, 2021, 3:07:29 AM8/6/21
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On 8/5/21 4:01 PM, Jimmy Johnson wrote:
> On 8/5/21 3:44 PM, John McCue wrote:
>
>> I could be wrong, but I think you cannot had /boot and
>> maybe / as btrfs.
>
> The install is all on one partition, I won't change that. I've never
> used separate partitions.

Okay, I reinstalled grub with all btrfs tools installed but installed
using ext4 and it's working, all my other systems are ext4, including
this one. I got "unknown system error" and it would not boot the btrfs
system. I can install grub to btrfs, but will it boot ext4 and btrfs? I
think it will, but I'm not sure!?!

Mike Small

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Aug 6, 2021, 3:40:13 PM8/6/21
to
Jimmy Johnson <field.e...@gmail.com> writes:

> On 8/5/21 12:54 PM, Jimmy Johnson wrote:
>
>> The btrfs file system is made. The slackware dvd iso is dated
>> 8/5/21, I wrote it to a flash drive and I'm in the installer
>> now. It's installing now, I see no changes in the installer, it did
>> identify my btrfs partition where I'm doing the install. So far it's
>> looking good, I'll keep you updated.
>
> It's looking like I can't do this.
> My grub is using a older kernel and can't mount btrfs. I don't know if
> I can update the kernel on sda1 and the slack btrfs install is on
> sda7, any advise or help?

Grub can boot kernels off of a btrfs system. It has modules for
that. There should have been an insmod line in your boot entry where you
tell Grub to load the btrfs grub module, similar to how you might have
had one to load its ext2 module. Then you would have needed the linux
btrfs module loaded into linux at initrd time so it can mount root from
btrfs.

It does work. I have a debian system system set up this way. In fact I
plan to install Slackware 15 into that same btrfs filesystem somehow
without reinitializing it, with slackware root being mounted from a
btrfs subvolume while keeping the existing debian on the same filesystem
intact and also bootable. I may be too optimistic, but I don't see any
of this having much to do with Slackware. It should be happy with
whatever filesystem I give it, the problem being between me and
grub/btrfs. Should be no problem, right?

- Mike Sm.

Jimmy Johnson

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Aug 6, 2021, 6:52:46 PM8/6/21
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On 8/6/21 12:40 PM, Mike Small wrote:

> Grub can boot kernels off of a btrfs system. It has modules for
> that. There should have been an insmod line in your boot entry where you
> tell Grub to load the btrfs grub module, similar to how you might have
> had one to load its ext2 module. Then you would have needed the linux
> btrfs module loaded into linux at initrd time so it can mount root from
> btrfs.

What is this insmod line? where can I find an example? I was thinking
there should be someway, but I could not find it. In my search I'm
finding way to much I don't understand. I see things like btrfs grub
module won't fit in the mbr. And btrfs-grub. By the way, I still use
legacy-grub.

> It does work. I have a debian system system set up this way. In fact I
> plan to install Slackware 15 into that same btrfs filesystem somehow
> without reinitializing it, with slackware root being mounted from a
> btrfs subvolume while keeping the existing debian on the same filesystem
> intact and also bootable. I may be too optimistic, but I don't see any
> of this having much to do with Slackware. It should be happy with
> whatever filesystem I give it, the problem being between me and
> grub/btrfs. Should be no problem, right?

I was thinking it would not be a problem, but now I won't know until I
see it. Maybe my system is not a good candidate for btrfs.
--
Jimmy Johnson

Mike Small

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Aug 9, 2021, 10:24:16 PM8/9/21
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Jimmy Johnson <ji...@none.none> writes:

> On 8/6/21 12:40 PM, Mike Small wrote:
>
>> Grub can boot kernels off of a btrfs system. It has modules for
>> that. There should have been an insmod line in your boot entry where you
>> tell Grub to load the btrfs grub module, similar to how you might have
>> had one to load its ext2 module. Then you would have needed the linux
>> btrfs module loaded into linux at initrd time so it can mount root from
>> btrfs.
>
> What is this insmod line? where can I find an example? I was thinking
> there should be someway, but I could not find it. In my search I'm
> finding way to much I don't understand. I see things like btrfs grub
> module won't fit in the mbr. And btrfs-grub. By the way, I still use
> legacy-grub.
>

Sorry if you'd mentioned in the original post that your attempt was
against grub 0.97 and I missed it. I imagine no one has updated that for
btrfs.

In case you are willing to use grub2 instead this is what my btrfs boot
entry looks like as generated by Debian. As usual with Debian
configuration it could use some toning down and tidying up:

menuentry "Debian" {
load_video
insmod gzio
insmod part_msdos
insmod btrfs
set root='hd0,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos5 --hint-efi=hd0,msdos5 --hint-baremetal=ahci0,msdos5 b906d859-dea8-4ae0-a5a7-ff349ad16df1
else
search --no-floppy --fs-uuid --set=root b906d859-dea8-4ae0-a5a7-ff349ad16df1
fi
echo 'Loading Linux 4.19.0-6-amd64 ...'
linux /boot/vmlinuz-4.19.0-6-amd64 root=UUID=b906d859-dea8-4ae0-a5a7-ff349ad16df1 ro
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-4.19.0-6-amd64
}

insmod must stand for insert module. This isn't a linux kernel module
but a module of grub 2 code. Grub 2 manages to be slightly less gargantuan
by using modules in a similar way to how Linux does.

- Mike Sm.


Jimmy Johnson

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Aug 10, 2021, 6:16:25 PM8/10/21
to
On 08/09/2021 07:24 PM, Mike Small wrote:
> Jimmy Johnson <ji...@none.none> writes:
>
>> On 8/6/21 12:40 PM, Mike Small wrote:
>>
>>> Grub can boot kernels off of a btrfs system. It has modules for
>>> that. There should have been an insmod line in your boot entry where you
>>> tell Grub to load the btrfs grub module, similar to how you might have
>>> had one to load its ext2 module. Then you would have needed the linux
>>> btrfs module loaded into linux at initrd time so it can mount root from
>>> btrfs.
>>
>> What is this insmod line? where can I find an example? I was thinking
>> there should be someway, but I could not find it. In my search I'm
>> finding way to much I don't understand. I see things like btrfs grub
>> module won't fit in the mbr. And btrfs-grub. By the way, I still use
>> legacy-grub.
>>
>
> Sorry if you'd mentioned in the original post that your attempt was
> against grub 0.97 and I missed it. I imagine no one has updated that for
> btrfs.

The system I use to install grub-legacy allows using the btrfs file
system, I don't know if it would do any good to install btrfs on it
though. I went back to using ext4 with a new install of slackware
current, I'll probably try this again at a later date, but there's just
to much going on right now.

> In case you are willing to use grub2 instead this is what my btrfs boot
> entry looks like as generated by Debian. As usual with Debian
> configuration it could use some toning down and tidying up:
>
> menuentry "Debian" {
> load_video
> insmod gzio
> insmod part_msdos
> insmod btrfs
> set root='hd0,msdos5'
> if [ x$feature_platform_search_hint = xy ]; then
> search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos5 --hint-efi=hd0,msdos5 --hint-baremetal=ahci0,msdos5 b906d859-dea8-4ae0-a5a7-ff349ad16df1
> else
> search --no-floppy --fs-uuid --set=root b906d859-dea8-4ae0-a5a7-ff349ad16df1
> fi
> echo 'Loading Linux 4.19.0-6-amd64 ...'
> linux /boot/vmlinuz-4.19.0-6-amd64 root=UUID=b906d859-dea8-4ae0-a5a7-ff349ad16df1 ro
> echo 'Loading initial ramdisk ...'
> initrd /boot/initrd.img-4.19.0-6-amd64
> }
>
> insmod must stand for insert module. This isn't a linux kernel module
> but a module of grub 2 code. Grub 2 manages to be slightly less gargantuan
> by using modules in a similar way to how Linux does.
>
> - Mike Sm.

Thanks for your post Mike, you've given me some things to think about.
--
Jimmy Johnson

Alien Linux - AMD A8-7600 - at sda11
Registered Linux User #380263
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