Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

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Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Robert Heller
Arg! I want to install Ubuntu 18.04.5 on a LVM volume in the LVM container on
my *existing* CentOS 6.10 system. The LVM container is on a software RAID disk
(simple mirror set). This *appears* not to be possible (?) since the Ubuntu
installer is not starting/seeing the RAID array and in live mode, mdadm
appears absent (question: what happens if I try to run apt-get install mdadm
on a live ISO system?).

WTF? Does Ubuntu 18.04 in fact not support software RAID during installation?

How am I supposed to procede?

My goal is to *migrate* the system, which is a combo desktop / server for my
home LAN from (now EOL) CentOS 6.10 to Ubuntu 18.04, but I really don't want
to completely wipe the disk which is what the Ubuntu installer would like to
do, because it thinks I have a pair of nearly empty 1.5TB disks, when really,
there are three partitions on each: a VFAT one set aside for a UEFI partition
(now empty/not used since my current MB is old school BIOS, but I plan on
upgrading the MB at some time, so I'm guessing I will need a UEFI partition),
a small EXT4 RAID pair for /boot, and the rest for a large LVM RAID pair for
everything else. I want to keep the CentOS 6.10 system functional for awhile
while I get the Ubuntu 18.04 system configured with all of the bits and pieces
I need (bind9, dhcpd, OpenLDAP, KVM, and more). The disks, being 1.5TB, have
GPT partition tables.

PS: I also have the Ubuntu 18.04.5 live server/install disk -- should I try
that instead?  Eg, does it have the RAID modules and mdadm in its init ramdisk
(appearently, the stock Ubuntu 18.04.5 disktop/install disk does not)?

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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Tony Arnold-3
Hi Robert,

On Sat, 2021-01-02 at 16:04 -0500, Robert Heller wrote:

> Arg! I want to install Ubuntu 18.04.5 on a LVM volume in the LVM
> container on
> my *existing* CentOS 6.10 system. The LVM container is on a software
> RAID disk
> (simple mirror set). This *appears* not to be possible (?) since the
> Ubuntu
> installer is not starting/seeing the RAID array and in live mode,
> mdadm
> appears absent (question: what happens if I try to run apt-get
> install mdadm
> on a live ISO system?).
It's not on the 20.04 live disk either as I just discovered. You can
install mdadm with the above command on the live ISO system, manually
assemble the disk array and proceed to the install. The installer
should see the logical volumes then.

TBH, I've not tried installing to a raid array. I have a single ssd for
the system and 2 spinning disks in a raid1 mdadm configuration. But
I've done the above when I'ved needed to do an off-line fsck of my home
volume.

> WTF? Does Ubuntu 18.04 in fact not support software RAID during
> installation?

Not OOTB by the looks of things.

> How am I supposed to procede?

See above.

Hope this is of some help.

Regards,
Tony.
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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Robert Heller
At Sat, 2 Jan 2021 21:16:17 +0000 "Ubuntu user technical support,  not for general discussions" <[hidden email]> wrote:

>
> Hi Robert,
>
> On Sat, 2021-01-02 at 16:04 -0500, Robert Heller wrote:
> > Arg! I want to install Ubuntu 18.04.5 on a LVM volume in the LVM
> > container on
> > my *existing* CentOS 6.10 system. The LVM container is on a software
> > RAID disk
> > (simple mirror set). This *appears* not to be possible (?) since the
> > Ubuntu
> > installer is not starting/seeing the RAID array and in live mode,
> > mdadm
> > appears absent (question: what happens if I try to run apt-get
> > install mdadm
> > on a live ISO system?).
>
> It's not on the 20.04 live disk either as I just discovered. You can
> install mdadm with the above command on the live ISO system, manually
> assemble the disk array and proceed to the install. The installer
> should see the logical volumes then.
>
> TBH, I've not tried installing to a raid array. I have a single ssd for
> the system and 2 spinning disks in a raid1 mdadm configuration. But
> I've done the above when I'ved needed to do an off-line fsck of my home
> volume.
>
> > WTF? Does Ubuntu 18.04 in fact not support software RAID during
> > installation?
>
> Not OOTB by the looks of things.

A serious flaw in my opinion....

>
> > How am I supposed to procede?
>
> See above.

Just that it seems seriously kludgy.  Wondering if I am going to have to
create and have on hand a *custom* crafted "rescue" image -- eg a version of
the Ubuntu installer disk with the software RAID modules and tools installed.

Of course I'll have to manually set up the network as well, since the box I am
installing on is also normally the DHCP server for the network.

I never had this issue with CentOS 4, 5, or 6 -- all of *their* installer
disks included the software RAID tools on the installer ISOs (and
automatically started the RAID arrays on boot).

>
> Hope this is of some help.
>
> Regards,
> Tony.

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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Ken D'Ambrosio
>> It's not on the 20.04 live disk either as I just discovered. You can
>> install mdadm with the above command on the live ISO system, manually
>> assemble the disk array and proceed to the install. The installer
>> should see the logical volumes then.

Pretty sure it's never been on there -- at least, some five years ago, I
was going down a similar road, and seem to recall bumping into the exact
same issue, with the exact same solution: installing to the live boot
environment for install (or, in my case, troubleshooting).

-Ken

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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Liam Proven
In reply to this post by Robert Heller
On Sat, 2 Jan 2021 at 22:07, Robert Heller <[hidden email]> wrote:
>
>
> WTF? Does Ubuntu 18.04 in fact not support software RAID during installation?

It used to.

https://help.ubuntu.com/community/Installation/SoftwareRAID

However, I have a feeling that it was dropped at some point, many years ago now.

There used to be "standard" and "alternate" CD ISOs and the alt was
needed for things like upgrading an existing system _from CD_ as
opposed to from the running system over the internet. Sadly I believe
the alternate ISO no longer exists.

> PS: I also have the Ubuntu 18.04.5 live server/install disk -- should I try
> that instead?  Eg, does it have the RAID modules and mdadm in its init ramdisk
> (appearently, the stock Ubuntu 18.04.5 disktop/install disk does not)?

Anyway, yes, I think you might get further with the server disk -- q.v.

https://support.us.ovhcloud.com/hc/en-us/articles/360006076940-How-to-Configure-Software-RAID-on-Ubuntu-18-04

JOOI: why the older version, since 20.04.01 is out now?

Although saying that, the new server install has its own fancy
disk-partitioning setup and it might be problematic.

I upgraded my 18.04 laptop to 20.04 recently and it went fairly well.
It tried to show me all my calendar notifications for the last 2 years
or something in one go, and made a lot of noise and locked the desktop
trying to display thousands of notifications. I dropped to text mode,
killed a few apps, but the desktop didn't come back, so I rebooted
from a vconsole. 2nd boot was fine and both GNOME and Unity are
working fine now. (As "fine" as GNOME ever works, anyway.)

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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Robert Heller
At Sun, 3 Jan 2021 01:42:45 +0100 "Ubuntu user technical support,  not for general discussions" <[hidden email]> wrote:

>
> On Sat, 2 Jan 2021 at 22:07, Robert Heller <[hidden email]> wrote:
> >
> >
> > WTF? Does Ubuntu 18.04 in fact not support software RAID during installation?
>
> It used to.
>
> https://help.ubuntu.com/community/Installation/SoftwareRAID
>
> However, I have a feeling that it was dropped at some point, many years ago now.
>
> There used to be "standard" and "alternate" CD ISOs and the alt was
> needed for things like upgrading an existing system _from CD_ as
> opposed to from the running system over the internet. Sadly I believe
> the alternate ISO no longer exists.

This is seriously dumb. I mean why drop these modules and tools? To save
space? Huh? I mean are they worried about the ISO not fitting on a 2gig thumb
drive? (Can you still get thumb drives that small?)

I have yet to see a desktop MB with fewer than 4 SATA ports, so having a RAID
array on a desktop is possible, pretty much out-of-the box, at least on the
hardware side. (Yes, I know laptops don't generally provide for multiple
internal hard drives, so a *laptop* with an internal RAID array for the system
disk is unlikely.)

>
> > PS: I also have the Ubuntu 18.04.5 live server/install disk -- should I try
> > that instead?  Eg, does it have the RAID modules and mdadm in its init ramdisk
> > (appearently, the stock Ubuntu 18.04.5 disktop/install disk does not)?
>
> Anyway, yes, I think you might get further with the server disk -- q.v.
>
> https://support.us.ovhcloud.com/hc/en-us/articles/360006076940-How-to-Configure-Software-RAID-on-Ubuntu-18-04
>
> JOOI: why the older version, since 20.04.01 is out now?

I do software development work (mostly with open source projects) and want to
maintain a level of downward compatibility on my development systems.  I want
to be able to support older (and still maintained!) systems.  *I* hate it when
open source projects require "bleeding edge" O/S, esp. when the projects are
not doing anything that really requires the "bleeding edge" O/S, but merely
because the developers are just developing on bleeding edge O/S.

It is not like 18.04 is going EOL anytime soon. And I will upgrade in a couple
of years. I have never seen any *good* reason to stand on the bleeding edge.

>
> Although saying that, the new server install has its own fancy
> disk-partitioning setup and it might be problematic.

Something I would rather avoid.  The "standard" Ubuntu installer is way to
user-friendly for my tastes.  I would really rather avoid an X11 based
installer if at all possible (it looks like it won't be with Ubuntu).

>
> I upgraded my 18.04 laptop to 20.04 recently and it went fairly well.
> It tried to show me all my calendar notifications for the last 2 years
> or something in one go, and made a lot of noise and locked the desktop
> trying to display thousands of notifications. I dropped to text mode,
> killed a few apps, but the desktop didn't come back, so I rebooted
> from a vconsole. 2nd boot was fine and both GNOME and Unity are
> working fine now. (As "fine" as GNOME ever works, anyway.)
>

Oh, I won't be having anything to do with GNOME or Unity -- just some minimual
bits from Mate.  (I find *all* of the "modern" desktop environments horribly
hard to use.)

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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Patrick Irvine
Just some 2 cents, but I know that LVM has MDRAID embedded in it.  I
wonder if MDRAID was dropped in favour of using LVM RAID?

Cheers,

Pat

On 2021-01-02 5:04 p.m., Robert Heller wrote:

> At Sun, 3 Jan 2021 01:42:45 +0100 "Ubuntu user technical support,  not for general discussions" <[hidden email]> wrote:
>
>> On Sat, 2 Jan 2021 at 22:07, Robert Heller <[hidden email]> wrote:
>>>
>>> WTF? Does Ubuntu 18.04 in fact not support software RAID during installation?
>> It used to.
>>
>> https://help.ubuntu.com/community/Installation/SoftwareRAID
>>
>> However, I have a feeling that it was dropped at some point, many years ago now.
>>
>> There used to be "standard" and "alternate" CD ISOs and the alt was
>> needed for things like upgrading an existing system _from CD_ as
>> opposed to from the running system over the internet. Sadly I believe
>> the alternate ISO no longer exists.
> This is seriously dumb. I mean why drop these modules and tools? To save
> space? Huh? I mean are they worried about the ISO not fitting on a 2gig thumb
> drive? (Can you still get thumb drives that small?)
>
> I have yet to see a desktop MB with fewer than 4 SATA ports, so having a RAID
> array on a desktop is possible, pretty much out-of-the box, at least on the
> hardware side. (Yes, I know laptops don't generally provide for multiple
> internal hard drives, so a *laptop* with an internal RAID array for the system
> disk is unlikely.)
>
>>> PS: I also have the Ubuntu 18.04.5 live server/install disk -- should I try
>>> that instead?  Eg, does it have the RAID modules and mdadm in its init ramdisk
>>> (appearently, the stock Ubuntu 18.04.5 disktop/install disk does not)?
>> Anyway, yes, I think you might get further with the server disk -- q.v.
>>
>> https://support.us.ovhcloud.com/hc/en-us/articles/360006076940-How-to-Configure-Software-RAID-on-Ubuntu-18-04
>>
>> JOOI: why the older version, since 20.04.01 is out now?
> I do software development work (mostly with open source projects) and want to
> maintain a level of downward compatibility on my development systems.  I want
> to be able to support older (and still maintained!) systems.  *I* hate it when
> open source projects require "bleeding edge" O/S, esp. when the projects are
> not doing anything that really requires the "bleeding edge" O/S, but merely
> because the developers are just developing on bleeding edge O/S.
>
> It is not like 18.04 is going EOL anytime soon. And I will upgrade in a couple
> of years. I have never seen any *good* reason to stand on the bleeding edge.
>
>> Although saying that, the new server install has its own fancy
>> disk-partitioning setup and it might be problematic.
> Something I would rather avoid.  The "standard" Ubuntu installer is way to
> user-friendly for my tastes.  I would really rather avoid an X11 based
> installer if at all possible (it looks like it won't be with Ubuntu).
>
>> I upgraded my 18.04 laptop to 20.04 recently and it went fairly well.
>> It tried to show me all my calendar notifications for the last 2 years
>> or something in one go, and made a lot of noise and locked the desktop
>> trying to display thousands of notifications. I dropped to text mode,
>> killed a few apps, but the desktop didn't come back, so I rebooted
>> from a vconsole. 2nd boot was fine and both GNOME and Unity are
>> working fine now. (As "fine" as GNOME ever works, anyway.)
>>
> Oh, I won't be having anything to do with GNOME or Unity -- just some minimual
> bits from Mate.  (I find *all* of the "modern" desktop environments horribly
> hard to use.)
>

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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Robert Heller
At Sun, 3 Jan 2021 02:42:22 -0800 "Ubuntu user technical support,  not for general discussions" <[hidden email]> wrote:

>
> Just some 2 cents, but I know that LVM has MDRAID embedded in it.  I
> wonder if MDRAID was dropped in favour of using LVM RAID?

LVM's "RAID" is not really RAID -- it is something else.


>
> Cheers,
>
> Pat
>
> On 2021-01-02 5:04 p.m., Robert Heller wrote:
> > At Sun, 3 Jan 2021 01:42:45 +0100 "Ubuntu user technical support,  not for general discussions" <[hidden email]> wrote:
> >
> >> On Sat, 2 Jan 2021 at 22:07, Robert Heller <[hidden email]> wrote:
> >>>
> >>> WTF? Does Ubuntu 18.04 in fact not support software RAID during installation?
> >> It used to.
> >>
> >> https://help.ubuntu.com/community/Installation/SoftwareRAID
> >>
> >> However, I have a feeling that it was dropped at some point, many years ago now.
> >>
> >> There used to be "standard" and "alternate" CD ISOs and the alt was
> >> needed for things like upgrading an existing system _from CD_ as
> >> opposed to from the running system over the internet. Sadly I believe
> >> the alternate ISO no longer exists.
> > This is seriously dumb. I mean why drop these modules and tools? To save
> > space? Huh? I mean are they worried about the ISO not fitting on a 2gig thumb
> > drive? (Can you still get thumb drives that small?)
> >
> > I have yet to see a desktop MB with fewer than 4 SATA ports, so having a RAID
> > array on a desktop is possible, pretty much out-of-the box, at least on the
> > hardware side. (Yes, I know laptops don't generally provide for multiple
> > internal hard drives, so a *laptop* with an internal RAID array for the system
> > disk is unlikely.)
> >
> >>> PS: I also have the Ubuntu 18.04.5 live server/install disk -- should I try
> >>> that instead?  Eg, does it have the RAID modules and mdadm in its init ramdisk
> >>> (appearently, the stock Ubuntu 18.04.5 disktop/install disk does not)?
> >> Anyway, yes, I think you might get further with the server disk -- q.v.
> >>
> >> https://support.us.ovhcloud.com/hc/en-us/articles/360006076940-How-to-Configure-Software-RAID-on-Ubuntu-18-04
> >>
> >> JOOI: why the older version, since 20.04.01 is out now?
> > I do software development work (mostly with open source projects) and want to
> > maintain a level of downward compatibility on my development systems.  I want
> > to be able to support older (and still maintained!) systems.  *I* hate it when
> > open source projects require "bleeding edge" O/S, esp. when the projects are
> > not doing anything that really requires the "bleeding edge" O/S, but merely
> > because the developers are just developing on bleeding edge O/S.
> >
> > It is not like 18.04 is going EOL anytime soon. And I will upgrade in a couple
> > of years. I have never seen any *good* reason to stand on the bleeding edge.
> >
> >> Although saying that, the new server install has its own fancy
> >> disk-partitioning setup and it might be problematic.
> > Something I would rather avoid.  The "standard" Ubuntu installer is way to
> > user-friendly for my tastes.  I would really rather avoid an X11 based
> > installer if at all possible (it looks like it won't be with Ubuntu).
> >
> >> I upgraded my 18.04 laptop to 20.04 recently and it went fairly well.
> >> It tried to show me all my calendar notifications for the last 2 years
> >> or something in one go, and made a lot of noise and locked the desktop
> >> trying to display thousands of notifications. I dropped to text mode,
> >> killed a few apps, but the desktop didn't come back, so I rebooted
> >> from a vconsole. 2nd boot was fine and both GNOME and Unity are
> >> working fine now. (As "fine" as GNOME ever works, anyway.)
> >>
> > Oh, I won't be having anything to do with GNOME or Unity -- just some minimual
> > bits from Mate.  (I find *all* of the "modern" desktop environments horribly
> > hard to use.)
> >
>
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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Liam Proven
In reply to this post by Robert Heller
On Sun, 3 Jan 2021 at 02:06, Robert Heller <[hidden email]> wrote:
>
> This is seriously dumb. I mean why drop these modules and tools? To save
> space? Huh? I mean are they worried about the ISO not fitting on a 2gig thumb
> drive? (Can you still get thumb drives that small?)

The Pareto Principle, AKA the 80:20 rule.

It's not a simple proportion.

The reason software gets so bloated is that although 80% of people
only want 20% of the functionality, they don't all want the _same_
20%. They all want a different 20%. When you add together a base and
all the other different 20%s that different audiences want, the result
is... well, a lot.

Ubuntu desktop and server have different foci, and Canonical seems to
be trying to broaden the gap. Also, it has ZFS now, and this
effectively replaces both LVM and mdraid.

So, stuff is taken out, too.

> I have yet to see a desktop MB with fewer than 4 SATA ports, so having a RAID
> array on a desktop is possible, pretty much out-of-the box, at least on the
> hardware side. (Yes, I know laptops don't generally provide for multiple
> internal hard drives, so a *laptop* with an internal RAID array for the system
> disk is unlikely.)

Just FWIW I have at least 2 Thinkpads with both a SATA bay and an
mSATA slot (X220 + T420), but it's neither here nor there really.

Laptops are where it's at now, and Ubuntu is an easy distro for
end-users, remember.

> I do software development work (mostly with open source projects) and want to
> maintain a level of downward compatibility on my development systems.  I want
> to be able to support older (and still maintained!) systems.  *I* hate it when
> open source projects require "bleeding edge" O/S, esp. when the projects are
> not doing anything that really requires the "bleeding edge" O/S, but merely
> because the developers are just developing on bleeding edge O/S.
>
> It is not like 18.04 is going EOL anytime soon. And I will upgrade in a couple
> of years. I have never seen any *good* reason to stand on the bleeding edge.

OK. Fair enough.

> Something I would rather avoid.  The "standard" Ubuntu installer is way to
> user-friendly for my tastes.  I would really rather avoid an X11 based
> installer if at all possible (it looks like it won't be with Ubuntu).

So, install Server and then just do `apt install xubuntu-desktop` or
something like that. It's easy enough; I've done it a lot in my
experiments to build a GNUstep-based (and ROX Desktop-based) remix.

> Oh, I won't be having anything to do with GNOME or Unity -- just some minimual
> bits from Mate.  (I find *all* of the "modern" desktop environments horribly
> hard to use.)

Xfce causes me the least grief. It does everything MATE does, smaller
and simpler, but also supports a vertical taskbar, which MATE can't.

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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Liam Proven
In reply to this post by Patrick Irvine
On Sun, 3 Jan 2021 at 11:44, Patrick Irvine <[hidden email]> wrote:
>
> Just some 2 cents, but I know that LVM has MDRAID embedded in it.  I
> wonder if MDRAID was dropped in favour of using LVM RAID?

No, it doesn't. This is wrong.

mdraid is entirely separate and distinct from LVM. You can build a
RAID volume from MDRAID and then put LVM on top of it and build an
encrypted filesystem in it, for instance.

LVM can build multi-drive volumes, including with redundancy, but that
is not the same thing at all.

Btrfs can do that as well, and you can also put Btrfs on top of LVM if
you wish. And put that on top of mdraid. They are all different and
independent.

This overlap is very confusing and I can see it's got you. No blame
there. It is hard to track.

This is why Ubuntu has gone with ZFS: ZFS includes the functionality
of mdraid, _and_ of LVM, _and_ of Btrfs, all in one single tool. I
have tried it and I am running it on a RasPi server that's blinking
away behind me right now. It is really very much easier than, say,
Btrfs or LVM.

I built a 5-drive ZRAID, formatted it and mounted it in a single
command. (I did have to write partition tables to the drives first,
but it was still hugely easier than doing it with mdraid etc.)

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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Robert Heller
In reply to this post by Liam Proven
At Mon, 4 Jan 2021 00:56:25 +0100 "Ubuntu user technical support,  not for general discussions" <[hidden email]> wrote:

>
> On Sun, 3 Jan 2021 at 02:06, Robert Heller <[hidden email]> wrote:
> >
> > This is seriously dumb. I mean why drop these modules and tools? To save
> > space? Huh? I mean are they worried about the ISO not fitting on a 2gig thumb
> > drive? (Can you still get thumb drives that small?)
>
> The Pareto Principle, AKA the 80:20 rule.
>
> It's not a simple proportion.
>
> The reason software gets so bloated is that although 80% of people
> only want 20% of the functionality, they don't all want the _same_
> 20%. They all want a different 20%. When you add together a base and
> all the other different 20%s that different audiences want, the result
> is... well, a lot.
>
> Ubuntu desktop and server have different foci, and Canonical seems to
> be trying to broaden the gap. Also, it has ZFS now, and this
> effectively replaces both LVM and mdraid.
>
> So, stuff is taken out, too.
>
> > I have yet to see a desktop MB with fewer than 4 SATA ports, so having a RAID
> > array on a desktop is possible, pretty much out-of-the box, at least on the
> > hardware side. (Yes, I know laptops don't generally provide for multiple
> > internal hard drives, so a *laptop* with an internal RAID array for the system
> > disk is unlikely.)
>
> Just FWIW I have at least 2 Thinkpads with both a SATA bay and an
> mSATA slot (X220 + T420), but it's neither here nor there really.
>
> Laptops are where it's at now, and Ubuntu is an easy distro for
> end-users, remember.
>
> > I do software development work (mostly with open source projects) and want to
> > maintain a level of downward compatibility on my development systems.  I want
> > to be able to support older (and still maintained!) systems.  *I* hate it when
> > open source projects require "bleeding edge" O/S, esp. when the projects are
> > not doing anything that really requires the "bleeding edge" O/S, but merely
> > because the developers are just developing on bleeding edge O/S.
> >
> > It is not like 18.04 is going EOL anytime soon. And I will upgrade in a couple
> > of years. I have never seen any *good* reason to stand on the bleeding edge.
>
> OK. Fair enough.
>
> > Something I would rather avoid.  The "standard" Ubuntu installer is way to
> > user-friendly for my tastes.  I would really rather avoid an X11 based
> > installer if at all possible (it looks like it won't be with Ubuntu).
>
> So, install Server and then just do `apt install xubuntu-desktop` or
> something like that. It's easy enough; I've done it a lot in my
> experiments to build a GNUstep-based (and ROX Desktop-based) remix.
>
> > Oh, I won't be having anything to do with GNOME or Unity -- just some minimual
> > bits from Mate.  (I find *all* of the "modern" desktop environments horribly
> > hard to use.)
>
> Xfce causes me the least grief. It does everything MATE does, smaller
> and simpler, but also supports a vertical taskbar, which MATE can't.

I don't like Xfce either -- it is what comes with Armbian, which is what I
installed on my Banana Pi M64 (quad core arm64 in a Raspberry Pi like form
factor). Like Mate it *insists* on a graphicial file manager. Something I
really, really do not want.  I have figured out how to hack Mate into not
have a graphicial file manager (I manually hacked the so-called
"required-components-list" to remove the components I really don't want).



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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Robert Heller
In reply to this post by Liam Proven
At Mon, 4 Jan 2021 00:56:25 +0100 "Ubuntu user technical support,  not for general discussions" <[hidden email]> wrote:

>
> So, install Server and then just do `apt install xubuntu-desktop` or
> something like that. It's easy enough; I've done it a lot in my
> experiments to build a GNUstep-based (and ROX Desktop-based) remix.

This does not work either.  The server ISO starts the RAID arrays and starts
the LVM volume group, but the installer does not give me any option to use the
existing RAID or LVM, but only gives me the option to create new RAID and/or
LVM volume groups.  Is there some special magic to get the *installer* to see
the *existing* RAID and LVM?

This is what my disk structure looks like:

sauron.deepsoft.com% cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sdb2[0] sda2[1]
      1003904 blocks [2/2] [UU]
     
md1 : active raid1 sdb3[0] sda3[1]
      1952118784 blocks super 1.2 [2/2] [UU]
      bitmap: 2/15 pages [8KB], 65536KB chunk

unused devices: <none>

md0 is the /boot file system (CentOS 6 uses Grub1, which does not understand
LVM)

md1 is a LVM volume group:

sauron.deepsoft.com% dir -lL /dev/mapper/
total 0
crw-rw----. 1 root root  10, 58 Jan  7 09:50 control
brw-rw----. 1 root disk 253, 11 Jan  7 09:50 sauron-c632guest
brw-rw----. 1 root disk 253, 12 Jan  7 09:50 sauron-c664guest
brw-rw----. 1 root disk 253,  1 Jan  7 09:50 sauron-c6_root
brw-rw----. 1 root disk 253, 14 Jan  7 09:50 sauron-c764guest
brw-rw----. 1 root disk 253,  6 Jan  7 09:50 sauron-distrocds
brw-rw----. 1 root disk 253,  5 Jan  7 09:50 sauron-dvdisos
brw-rw----. 1 root disk 253,  7 Jan  7 09:50 sauron-extra
brw-rw----. 1 root disk 253, 18 Jan  7 09:50 sauron-gollumC7boot
brw-rw----. 1 root disk 253, 17 Jan  7 09:50 sauron-gollumC7root
brw-rw----. 1 root disk 253,  2 Jan  7 09:50 sauron-home
brw-rw----. 1 root disk 253, 13 Jan  7 09:50 sauron-localrepo
brw-rw----. 1 root disk 253, 15 Jan  7 09:50 sauron-msbuilder
brw-rw----. 1 root disk 253,  8 Jan  7 09:50 sauron-SourceManagementC5
brw-rw----. 1 root disk 253,  4 Jan  7 09:50 sauron-Stuff
brw-rw----. 1 root disk 253,  0 Jan  7 09:50 sauron-swap
brw-rw----. 1 root disk 253,  9 Jan  7 09:50 sauron-ub1204_32
brw-rw----. 1 root disk 253, 10 Jan  7 10:06 sauron-ub1204_64
brw-rw----. 1 root disk 253, 19 Jan  7 09:50 sauron-ubuntu_root
brw-rw----. 1 root disk 253, 16 Jan  7 09:50 sauron-videoholding
brw-rw----. 1 root disk 253,  3 Jan  7 09:50 sauron-wine

I would like to install Ubuntu 18.04 onto sauron-ubuntu_root, leaving
everthing else alone.


I guess I need some other install hack.  What are my options?  I suppose I
could swap in a spare disk and install there and then copy it over and
manually hack the boot setup...  I would really avoid that, since it is such a
pain.  (I don't know, but installing Slackware from a shoebox full of floppies
was actually easier.)

It appears that Ubuntu is looking like a much harder to deal with O/S than I
thought...

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Deepwoods Software        -- Custom Software Services
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Re: Arg: no mdadm on Ubuntu 18.04.5 Desktop install disk?

Tom H-4
In reply to this post by Robert Heller
On Sat, Jan 2, 2021 at 10:07 PM Robert Heller <[hidden email]>
wrote:
>
> Arg! I want to install Ubuntu 18.04.5 on a LVM volume in the LVM
> container on my *existing* CentOS 6.10 system. The LVM container
> is on a software RAID disk (simple mirror set). This *appears*
> not to be possible (?) since the Ubuntu installer is not
> starting/seeing the RAID array and in live mode, mdadm appears
> absent (question: what happens if I try to run apt-get install
> mdadm on a live ISO system?).

You can install mdadm while booted from the disk/stick and use it.

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