CentOS - Feb 2015 - CentOS 7: software RAID 5 array with 4 disks and no spares?

On Wed, Feb 18, 2015 at 4:20 PM,  <m.roth at 5-cent.us>
wrote:
> Niki Kovacs wrote:
>> Le 18/02/2015 23:12,
>> close, but then, for mysterious reasons, Red Hat decided to cripple it
>> into oblivion. Go figure.
>
> One word: desktop. That's what they want to conquer next.
OK well there's a really long road to get to that pie in the sky. I
don't see it happening because it seems there's no mandate to
basically tell people what they can't have, instead it's well, we'll
have a little of everything.

Desktop OS that are the conquerers now? Their installers don't offer
100's of layout choices. They offer 1-2, and they always work rock
solid, no crashing, no user confusion, essentially zero bugs. The code
is brain dead simple, and that results in stability.

*shrug*

Long road. Long long long. Tunnel. No light. The usability aspects are
simply not taken seriously by the OS's as a whole. It's only taken
seriously by DE's and they get loads of crap for every change they
want to make. Until there's a willingness to look at 16 packages as a
whole rather than 1 package at a time, desktop linux has no chance.
The very basic aspects of how to partition, assemble, and boot and
linux distro aren't even agreed upon. Fedora n+1 has problems
installing after Fedora n. And it's practically a sport for each
distro to step on an existing distros installer. This is
technologically solved, just no one seems to care to actually
implement something more polite.

OS X? It partitions itself, formats a volume, sets the type code,
writes some code into NVRAM, in order to make the reboot automatically
boot the Windows installer from a USB stick. It goes out of it's way
to invite the foreign OS.

We can't even do that with the same distro, different version. It
should be embarrassing but no one really cares enough to change it.
It's thankless work in the realm of polish. But a huge amount of
success for a desktop OS comes from polish.

> We also pretty much don't use any drives under 1TB. The upshot is we
had
> custom scripts for > 500GB, which made 4 partitions - /boot (1G, to fit
> with the preupgrade), swap (2G), / (497G - and we're considering
> downsizing that to 250G, or maybe 150G) and the rest in another partition
> for users' data and programs. The installer absolutely does *not* want
to
> do what we want. We want swap - 2G - as the *second* partition. But if we
> use the installer, as soon as we create the third partition, of 497GB, for
> /, it immediately reorders them, so that / is second.
I'm open to having my mind changed on this, but I'm not actually
understanding why it needs to be in the 2nd slot, other than you want
it there, which actually isn't a good enough reason. If there's a good
reason for it to be in X slot always, for everyone, including
anticipating future use, then that's a feature request and it ought to
get fixed. But if it's a specific use case, well yeah you get to
pre-partition and then install.

-- 
Chris Murphy

On 19.02.2015 06:28, Chris Murphy wrote:
> On Wed, Feb 18, 2015 at 4:20 PM,  <m.roth at 5-cent.us> wrote:
>> Niki Kovacs wrote:
>>> Le 18/02/2015 23:12,
> 
>>> close, but then, for mysterious reasons, Red Hat decided to cripple
it
>>> into oblivion. Go figure.
>>
>> One word: desktop. That's what they want to conquer next.
> 
> OK well there's a really long road to get to that pie in the sky. I
> don't see it happening because it seems there's no mandate to
> basically tell people what they can't have, instead it's well,
we'll
> have a little of everything.
> 
> Desktop OS that are the conquerers now? Their installers don't offer
> 100's of layout choices. They offer 1-2, and they always work rock
> solid, no crashing, no user confusion, essentially zero bugs. The code
> is brain dead simple, and that results in stability.
> 
> *shrug*
> 
> Long road. Long long long. Tunnel. No light. The usability aspects are
> simply not taken seriously by the OS's as a whole. It's only taken
> seriously by DE's and they get loads of crap for every change they
> want to make. Until there's a willingness to look at 16 packages as a
> whole rather than 1 package at a time, desktop linux has no chance.
> The very basic aspects of how to partition, assemble, and boot and
> linux distro aren't even agreed upon. Fedora n+1 has problems
> installing after Fedora n. And it's practically a sport for each
> distro to step on an existing distros installer. This is
> technologically solved, just no one seems to care to actually
> implement something more polite.
> 
> OS X? It partitions itself, formats a volume, sets the type code,
> writes some code into NVRAM, in order to make the reboot automatically
> boot the Windows installer from a USB stick. It goes out of it's way
> to invite the foreign OS.
> 
> We can't even do that with the same distro, different version. It
> should be embarrassing but no one really cares enough to change it.
> It's thankless work in the realm of polish. But a huge amount of
> success for a desktop OS comes from polish.
I think the problem is that you simply have to draw a distinction
between technology and product.
The rise of the Linux desktop will never happen because Linux is not a
product but a technology and as a result has to be a jack of all trades.
The reason Apple is so successful I believe is because they understood
more than others that people don't care about technology but want one
specific consistent experience. They don't core how the harddisk is
partitioned.
So I can see the rise of the "X desktop" but only if X is willing to
have its own identity an eschew the desire to be compatible with
everything else or cater to both casual users and hard-core admin types.
In other words the "X Desktop" would have to be a very opinionated
product rather than a highly flexible technology.
>> We also pretty much don't use any drives under 1TB. The upshot is
we had
>> custom scripts for > 500GB, which made 4 partitions - /boot (1G, to
fit
>> with the preupgrade), swap (2G), / (497G - and we're considering
>> downsizing that to 250G, or maybe 150G) and the rest in another
partition
>> for users' data and programs. The installer absolutely does *not*
want to
>> do what we want. We want swap - 2G - as the *second* partition. But if
we
>> use the installer, as soon as we create the third partition, of 497GB,
for
>> /, it immediately reorders them, so that / is second.
> 
> I'm open to having my mind changed on this, but I'm not actually
> understanding why it needs to be in the 2nd slot, other than you want
> it there, which actually isn't a good enough reason. If there's a
good
> reason for it to be in X slot always, for everyone, including
> anticipating future use, then that's a feature request and it ought to
> get fixed. But if it's a specific use case, well yeah you get to
> pre-partition and then install.
> 
When I was younger I cared about where exactly each partition was
positioned but nowadays I refer to all my file systems using the uuid so
I don't really care anymore if / is the second or fifth partition. The
same is true for network interfaces. Since I mostly deal with physical
interfaces on Hypervisors only these days and there I am more interested
in bridges rather than the nics themselves I couldn't care less if the
interface is named eth0 or enp2something. I tend to think more in terms
of logical resources these days rather than physical ones.

Regards,
  Dennis

On Thu, Feb 19, 2015 at 5:47 AM, Dennis Jacobfeuerborn
<dennisml at conversis.de> wrote:
> I think the problem is that you simply have to draw a distinction
> between technology and product.
> The rise of the Linux desktop will never happen because Linux is not a
> product but a technology and as a result has to be a jack of all trades.
I'm unconvinced. True, Chromebooks uses the linux kernel, and thus it
qualifies, sorta, as Linux desktop. But this is something analogous to
OS X using a FOSS kernel and some other BSD stuff, but the bulk of it
is proprietary. Maybe Chrome isn't quite that proprietary, but it's
not free either. And Chrome OS definitely is not jack of all trades.
What it can run is very narrow in scope right now.


> The reason Apple is so successful I believe is because they understood
> more than others that people don't care about technology but want one
> specific consistent experience. They don't core how the harddisk is
> partitioned.
> So I can see the rise of the "X desktop" but only if X is willing
to
> have its own identity an eschew the desire to be compatible with
> everything else or cater to both casual users and hard-core admin types.
> In other words the "X Desktop" would have to be a very
opinionated
> product rather than a highly flexible technology.
Hmm, well Apple as a pretty good understanding what details are and
aren't important to most people. That is, they discriminate. People do
care about technologies like disk encryption, but they don't care
about the details of how to enable or manage it. Hence we see both iOS
and Android enable it by default now. Change the screen lock password,
and it also changes the encryption unlock password *while removing*
the previous password all in one step. On all conventional Linux
distributions, this is beyond confusing and is totally sysadmin
territory. I'd call it a bad experience.

OK so that's mobile vs desktop, maybe not fair. However, OS X has one
button click full disk encryption as opt in post-install (and opt out
after). This is done with live conversion. The user can use the
computer normally while conversion occurs, they can put the system to
sleep, and even reboot it, and will resume conversion when the system
comes back up. Decrypt conversion works the same way. They are poised
to make full disk encryption a default behavior, without having
changed the user experience at all, in the next major release of the
software. I don't know whether they'll do it, but there are no
technical or usability impediments.

Linux distros experience on this front is terrible. Why? Linux OS's
don't have a good live conversion implementation (some people have
tried this and have hacks, but no distro has adopted this); but Ok the
installer could just enable it by default, obviating conversion. But
there's no one really looking at the big picture, looking at dozens of
packages, how this affects them all from the installer password
policy, to Gnome and KDE. You'd need the add user GUI tools to be able
to change both user login and encryption passphrase passwords, to keep
them in sync, and remove the old one. And currently LUKS has this 8
slot limit, which is probably not a big problem, but might be a
sufficient barrier in enough cases that this needs extending.

And so on...



-- 
Chris Murphy