[gentoo-user] OT: Is EVMS dead?

[gentoo-user] OT: Is EVMS dead?

[James]

Hello,

I do not read as much as I should, but, I stumbled across this page [1]
that suggests that EVMS is dead. I see it is in portage, but is it
slated for the trash, as time moves forward? Sure it's Ubuntu site, but
they claim EVMS is unmaintained, if you read further down the page.


[1] https://wiki.ubuntu.com/Evms


opinions?


James




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Re: [gentoo-user] OT: Is EVMS dead?

[Albert Hopkins]

On Mon, 2007-11-05 at 17:29 +0000, James wrote:
> Hello,
> 
> I do not read as much as I should, but, I stumbled across this page [1]
> that suggests that EVMS is dead. I see it is in portage, but is it
> slated for the trash, as time moves forward? Sure it's Ubuntu site, but
> they claim EVMS is unmaintained, if you read further down the page.

>From evms.sf.net:

"The current stable version of EVMS is 2.5.5. It was released on
February 26, 2006."

That's 3 months shy of 2 years.  Also read the following thread from
their -dev ML:

http://marc.info/?l=evms-devel&m=119078823017821&w=2



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Re: [gentoo-user] OT: Is EVMS dead?

[Dirk Heinrichs]

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Am Montag, 5. November 2007 schrieb James:
> Hello,
>
> I do not read as much as I should, but, I stumbled across this page [1]
> that suggests that EVMS is dead. I see it is in portage, but is it
> slated for the trash, as time moves forward? Sure it's Ubuntu site, but
> they claim EVMS is unmaintained, if you read further down the page.

Well, it is currently unmaintained. But does this mean it's dead? I don't 
think so. All it needs is a new maintainer. On to what ubuntu writes:

"...the update manager will recommend that you remove it, failing to do so can 
render your computer unbootable (or at least, incredibly slow)."

Why should it get unbootable? Or slower than before?

What they write about bd_claim is completely true and it can happen that with 
EVMS a device can be claimed multiple times. BUT ONLY IF YOU APPLY EVMS' 
BD_CLAIM PATCH!! which they obviously did -> their own fault.

"EVMS depends on the extremely outdated and unmaintained GTK+ 1.2 libraries, 
it has not been updated to the GTK+ 2.0 series (currently 2.12.0)"

AFAIK, debian has a patch to switch EVMS to gtk+ 2.x. Why doesn't ubuntu use 
it. Anyway, not a problem for Gentoo, slots to the rescue.

"EVMS does not support the vanilla Linux 2.6 kernel, and instead requires that 
the bd_claim feature be patched out (source: [WWW] 
http://evms.sourceforge.net/install/kernel.html#bdclaim)"

BULLSHIT!! They obviously didn't read that section completely. I use EVMS on 
vanilla 2.6 kernels w/o the bd_claim patch.

However, feel free to step up as a new maintainer :-)

Bye...

	Dirk

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[gentoo-user] Re: OT: Is EVMS dead?

[James]

Dirk Heinrichs <dirk.heinrichs <at> online.de> writes:


> Well, it is currently unmaintained. But does this mean it's dead? I don't 
> think so. All it needs is a new maintainer. On to what ubuntu writes:

> However, feel free to step up as a new maintainer 

> 	Dirk


Hello,

I have only used EVMS on a few occasions. I'd not be the one to maintain this
package...... Wonder why IBM pulled resources from it?



James



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Re: [gentoo-user] OT: Is EVMS dead?

[Eric S. Johansson]

Albert Hopkins wrote:
> On Mon, 2007-11-05 at 17:29 +0000, James wrote:
>> Hello,
>>
>> I do not read as much as I should, but, I stumbled across this page [1]
>> that suggests that EVMS is dead. I see it is in portage, but is it
>> slated for the trash, as time moves forward? Sure it's Ubuntu site, but
>> they claim EVMS is unmaintained, if you read further down the page.
> 
>>From evms.sf.net:
> 
> "The current stable version of EVMS is 2.5.5. It was released on
> February 26, 2006."
> 
> That's 3 months shy of 2 years.  Also read the following thread from
> their -dev ML:
> 
> http://marc.info/?l=evms-devel&m=119078823017821&w=2

given that I frequently play the role of the heretic (complete with burn scars 
all over my body and various bits of damage from the weapons of true believers) 
I think it's a good thing that EVMS is slated for the trash heap.  It's a 
classic example of "second system syndrome" as defined by "the mythical Man 
month".  It's overly complicated, poorly documented, and has a terrible user 
interface that only a geek would even consider using.

Having said that, I also think LVMS suffers from many if not all of the same 
problems that plagued EVMS.  it is been around for years and still the 
documentation on how to perform common operations is lacking.  It's a chicken 
and egg problem.  You need to understand LVMS in order to understand the 
documentation and then you can't explain it to anyone else.  Every time I've 
used LVMS, it takes me the same number of hours to relearn the same old pieces 
of obscure command syntax and become comfortable that I'm not going to trash my 
disk.  As a result, I don't use LVMS either.

I don't see a compelling case for using LVMS and it kin unless you're running a 
multiple disk array with different segments mounted as raid arrays.  Then you 
can justify the expense of your labor in understanding how to use LVMS.  Using 
it on a small system like a laptop or desktop with only a couple drives, not 
worth it.  Even if you're just using simple mirroring, it's still not worth it. 
  Here's a simple example why not.  If you machine dies and your backups are 
"inadequate", you may want to try and recover the disc by putting it into 
another system.  How?  If you didn't back up a bunch of magic information from 
the original system's /etc directory, you're well and truly screwed.  But even 
if you have the information, you may still be screwed if you can't find the 
documentation which tells you how to incorporate the LVMS configuration data 
into the new system.  this is the kind of high risk error prone thing that a 
command should do, not a human.

This situation really sucks.  LVMS can be really nice when you need it but 
unfortunately a lack of documentation, use examples written for people who don't 
live with LVMS but once or twice a year, and a nice GUI for translating what the 
user wants to do into LVMS commands keep LVMS inaccessible and frustrating to 
use by many

---eric (heretic by thought, deed, and graffiti)


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Re: [gentoo-user] OT: Is EVMS dead?

[felix]

On Mon, Nov 05, 2007 at 06:01:28PM -0500, Eric S. Johansson wrote:

> Here's a simple example why not.  If you machine dies and your
> backups are "inadequate", you may want to try and recover the disc
> by putting it into another system.  How?  If you didn't back up a
> bunch of magic information from the original system's /etc
> directory, you're well and truly screwed.

Are you sure about that?  I have two offline backups, each is two
disks on firewire / USB external disks.  Last time I connected one of
them, I had the two cables swappped, and LVM still pciked them up
correctly.  I am not aware of any magic info on the main system.

But I don't use LVM much; once set up, I leave it alone.  Right now I
ought to expand a couple of partitions which are at 93% or so.  The
docs say I should be able to do this with the partitions mounted, but
on eof them is /usr and I am reluctant to either try it or to bring it
down to single user mode.

-- 
            ... _._. ._ ._. . _._. ._. ___ .__ ._. . .__. ._ .. ._.
     Felix Finch: scarecrow repairman & rocket surgeon / felix@crowfix.com
  GPG = E987 4493 C860 246C 3B1E  6477 7838 76E9 182E 8151 ITAR license #4933
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Re: [gentoo-user] OT: Is EVMS dead?

[Neil Bothwick]

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On Mon, 05 Nov 2007 18:01:28 -0500, Eric S. Johansson wrote:

> If you machine dies and your backups are 
> "inadequate", you may want to try and recover the disc by putting it
> into another system.  How?  If you didn't back up a bunch of magic
> information from the original system's /etc directory, you're well and
> truly screwed.

Or you could run vgscan, provided everything is not auto-detected before
you get the chance. 


-- 
Neil Bothwick

One difference between a man and a machine is that a machine is quiet
when well oiled.

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Re: [gentoo-user] OT: Is EVMS dead?

[Albert Hopkins]

On Mon, 2007-11-05 at 18:01 -0500, Eric S. Johansson wrote:

> 
> given that I frequently play the role of the heretic (complete with burn scars 
> all over my body and various bits of damage from the weapons of true believers) 
> I think it's a good thing that EVMS is slated for the trash heap.  It's a 
> classic example of "second system syndrome" as defined by "the mythical Man 
> month".  It's overly complicated, poorly documented, and has a terrible user 
> interface that only a geek would even consider using.
> 
> Having said that, I also think LVMS suffers from many if not all of the same 
> problems that plagued EVMS.  it is been around for years and still the 
> documentation on how to perform common operations is lacking.  It's a chicken 
> and egg problem.  You need to understand LVMS in order to understand the 
> documentation and then you can't explain it to anyone else.  Every time I've 
> used LVMS, it takes me the same number of hours to relearn the same old pieces 
> of obscure command syntax and become comfortable that I'm not going to trash my 
> disk.  As a result, I don't use LVMS either.
> 
I've never used EVMS so I can't comment at all on it.  However I have
been using LVM for years and one of the few good things I can say about
it is that its pretty small, easy, and predictable. In fact one of the
negative things I'd have to say about it is that it's *too* simple (a LV
defrag tool would be nice).  I really don't understand the complexity
you speak of.  It's pretty well documented, and has a fairly high
user-base.

I do agree though that, based on this ML and IRC discussions, many times
I'll see a person who wants to use LVM and perhaps maybe they don't need
it, and they get frustrated because they're using the wrong tool for the
job.  Myself: I have a 8 2-disk RAID volumes with LVM on top.  If I need
to expand my VG, I just pop in a couple of new drives, to an lvextend on
a volume and then "mount -o remount,resize" and voila! 

On another machine I have xen and I have 2 VGs: a set of disks for the
Host and a set for the VMs.  I have some VMs in a DMZ, and I can't reach
them from the host, but I use LVM to create snapshots of their disks and
make backup of them.  LVM makes it damn easy. In some ways LVM is like a
poor-man's SAN for Xen VMs.  You can carve out a LV, assign it to a VM,
and resize, hot-add or hot-remove them as you please.

But again, the average person with a single disk running on a laptop
computer probably has no use for LVM.

Pretty much every major "server" OS has volume management (including
Windows) because a lot of users at that level need it.  Linu LVM, I
think, is very similar to HP-UX LVM at the command level.

Anyway YMMV.
--
Albert W. Hopkins

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Re: [gentoo-user] OT: Is EVMS dead?

[Eric S. Johansson]

Neil Bothwick wrote:
> On Mon, 05 Nov 2007 18:01:28 -0500, Eric S. Johansson wrote:
> 
>> If you machine dies and your backups are 
>> "inadequate", you may want to try and recover the disc by putting it
>> into another system.  How?  If you didn't back up a bunch of magic
>> information from the original system's /etc directory, you're well and
>> truly screwed.
> 
> Or you could run vgscan, provided everything is not auto-detected before
> you get the chance. 

if I remember correctly, and it has been quite a while, vgscan only works if 
your lvm.conf is intact.  Merging one lvm.conf with one from another machine is 
tricky and is not always successful unless you are living with LVM and then it 
is only mostly successful.  if you don't have your original lvm.conf, again if 
memory serves, you need to go rooting through the first fewsectors of your disk 
to find what looks like it might be perhaps, possibly the data you need.

in looking for examples for this kind of recovery process, I came across a 
rather nice page from our friends at Novell.

http://www.novell.com/coolsolutions/appnote/19386.html

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Re: [gentoo-user] OT: Is EVMS dead?

[Dirk Heinrichs]

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Am Dienstag, 6. November 2007 schrieb felix@crowfix.com:

> But I don't use LVM much; once set up, I leave it alone.  Right now I
> ought to expand a couple of partitions which are at 93% or so.  The
> docs say I should be able to do this with the partitions mounted, but
> on eof them is /usr and I am reluctant to either try it or to bring it
> down to single user mode.

Just do it. All filesystems nowadays support online expand. Just use lvresize 
+ the resize tool of the fs you use.

BTW: With EVMS, you wouldn't hav to use two commands, but only one (except for 
ext2/3, online resize capabality was added to this fs after EVMS went 
unmaintained).

Bye...

	Dirk

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Re: [gentoo-user] OT: Is EVMS dead?

[Dirk Heinrichs]

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Am Dienstag, 6. November 2007 schrieb Eric S. Johansson:
> Albert Hopkins wrote:
> > On Mon, 2007-11-05 at 17:29 +0000, James wrote:
> >> Hello,
> >>
> >> I do not read as much as I should, but, I stumbled across this page [1]
> >> that suggests that EVMS is dead. I see it is in portage, but is it
> >> slated for the trash, as time moves forward? Sure it's Ubuntu site, but
> >> they claim EVMS is unmaintained, if you read further down the page.
> >>
> >>From evms.sf.net:
> >
> > "The current stable version of EVMS is 2.5.5. It was released on
> > February 26, 2006."
> >
> > That's 3 months shy of 2 years.  Also read the following thread from
> > their -dev ML:
> >
> > http://marc.info/?l=evms-devel&m=119078823017821&w=2
>
> given that I frequently play the role of the heretic (complete with burn
> scars all over my body and various bits of damage from the weapons of true
> believers) I think it's a good thing that EVMS is slated for the trash
> heap.  It's a classic example of "second system syndrome" as defined by
> "the mythical Man month".

Errh, what?

> It's overly complicated, poorly documented, and 
> has a terrible user interface that only a geek would even consider using.

What's wrong with the excelent user guide on the project's site? Which of the 
three UIs exactly do you think is horrible?

Bye...

	Dirk

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Re: [gentoo-user] Re: OT: Is EVMS dead?

[Dirk Heinrichs]

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Am Montag, 5. November 2007 schrieb James:

> I have only used EVMS on a few occasions. I'd not be the one to maintain
> this package...... Wonder why IBM pulled resources from it?

Don't know. Maybe they thought it's feature complete and free of bugs.

Bye...

	Dirk

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[gentoo-user] Re: OT: Is EVMS dead?

[Alexander Skwar]

Eric S. Johansson <esj@harvee.org> wrote:

> Neil Bothwick wrote:
>> On Mon, 05 Nov 2007 18:01:28 -0500, Eric S. Johansson wrote:
>> 
>>> If you machine dies and your backups are
>>> "inadequate", you may want to try and recover the disc by putting it
>>> into another system.  How?  If you didn't back up a bunch of magic
>>> information from the original system's /etc directory, you're well and
>>> truly screwed.
>> 
>> Or you could run vgscan, provided everything is not auto-detected before
>> you get the chance.
> 
> if I remember correctly, and it has been quite a while, vgscan only works
> if
> your lvm.conf is intact.  Merging one lvm.conf with one from another
> machine is tricky and is not always successful unless you are living with
> LVM and then it
> is only mostly successful.  if you don't have your original lvm.conf,
> again if memory serves, you need to go rooting through the first
> fewsectors of your disk to find what looks like it might be perhaps,
> possibly the data you need.

What the heck are you talking about?

All that's needed to be done is a vgscan followed by a vgchange. That's
it.

> in looking for examples for this kind of recovery process, I came across a
> rather nice page from our friends at Novell.

"friends"? Novell, that's the enemy!

Alexander Skwar

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Re: [gentoo-user] OT: Is EVMS dead?

[Neil Bothwick]

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On Tue, 06 Nov 2007 00:18:47 -0500, Eric S. Johansson wrote:

> if I remember correctly, and it has been quite a while, vgscan only
> works if your lvm.conf is intact.

You remember incorrectly. lvm.conf is not needed to use LVM. It
configures some aspects of LVM, such as filtering out devices to speed up
scanning and setting snapshot policies, but it is not needed to access
the data on the LVM volumes.

The only time I have had a problem accessing the data from an LVM on a
different machine is when both systems used the same volume group name,
which is solved by renaming one of them.


-- 
Neil Bothwick

As a computer, I find your faith in technology amusing.

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Re: [gentoo-user] OT: Is EVMS dead?

[Florian Philipp]

Albert Hopkins schrieb:

> 
> But again, the average person with a single disk running on a laptop
> computer probably has no use for LVM.
> 

Actually I'm very happy I've chosen LVM for my laptop because I didn't 
know that I would keep 20GB worth of videos on my home partition when 
I've made up the partitioning scheme.
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Re: [gentoo-user] OT: Is EVMS dead?

[Eric Martin]

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Hash: SHA1

Neil Bothwick wrote:
> On Tue, 06 Nov 2007 00:18:47 -0500, Eric S. Johansson wrote:
>
>> if I remember correctly, and it has been quite a while, vgscan
>> only works if your lvm.conf is intact.
>
> You remember incorrectly. lvm.conf is not needed to use LVM. It
> configures some aspects of LVM, such as filtering out devices to
> speed up scanning and setting snapshot policies, but it is not
> needed to access the data on the LVM volumes.
>
> The only time I have had a problem accessing the data from an LVM
> on a different machine is when both systems used the same volume
> group name, which is solved by renaming one of them.
>
>
I had a laptop running LVM and then the BIOS told me to backup my data
because my drive was going to die.  I pulled the drive, popped it into
a USB enclosure and brought it to my desktop to rsync it to an eSATA
drive.  All I had to do was vgscan and vgchange -a y and I was up and
running.  Actually, I too had a problem with my VG's named the same
thing.  It wasn't a problem to access different LV's but I changed the
VG anyway.  As a pointer for people, you might want to append the name
of your box to your VG, that way it will be (probably) unique on your
network.  Also you'll know where you are if you need to do a backup
like I had to.

Eric
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Re: [gentoo-user] OT: Is EVMS dead?

[Alan]

> mirroring, it's still not worth it.  Here's a simple example why not.  If 
> you machine dies and your backups are "inadequate", you may want to try and 
> recover the disc by putting it into another system.  How?  If you didn't 
> back up a bunch of magic information from the original system's /etc 
> directory, you're well and truly screwed.  But even if you have the 

Actually this isn't strictly  true.  I've had issues where I've "lost"
my arrays under normal booting (may be due to non-bd patched system or
something, but basically I'd reboot and the kernel would grab one disk
of my 2xRAID5 arrays acting-as-one-big-ass-disk setup and that would
fail one RAID5, causing EVMS to tell me the array was b0rked... very
nerve-wracking when you have 600G of non-backed up media....).  Anyway,
I've rebooted with a gentoo live CD, ran evmsn from the command line,
selected the evms partition and it's all up and going, without accessing
anything on the host machine.

-- 
Alan <alan@ufies.org> - http://arcterex.net
--------------------------------------------------------------------
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Re: [gentoo-user] OT: Is EVMS dead?

[Eric S. Johansson]

Dirk Heinrichs wrote:

>> heap.  It's a classic example of "second system syndrome" as defined by
>> "the mythical Man month".
> 
> Errh, what?

rtfb  it was published in 1972, is still in print and the first five chapters 
are as relevant today as they were when it was first published.  It explains why 
software projects fail.  I think it's pretty sad when failings in an industry 
recognized 35 years ago are still happening today.

Brooks says write one system to throw away because you are going to anyway.  The 
first time you implement, you don't understand the problem and you frequently 
leave out functionality or implement things in a clumsy or incorrect way.  This 
next implementation you, in theory, understand the problem and can do a better 
job which leads us to...

second system syndrome.  when you implement a system for the second time you 
think you have the problem fully understood, add lots of features and 
capabilities and end up with a disaster on your hands because you over estimated 
your capabilities.

which is really Fred Brooks's way of saying write two system to throw away 
because you're going to anyway.

a great example of this is Microsoft.  They rarely get anything right until the 
third version (implementation).  Other examples are easily found if you just look.

> 
>> It's overly complicated, poorly documented, and 
>> has a terrible user interface that only a geek would even consider using.
> 
> What's wrong with the excelent user guide on the project's site? Which of the 
> three UIs exactly do you think is horrible?

could never get the containers nesting right.  If the instructions on how to use 
an LVM can't be explained on a postcard, you don't understand how to communicate 
with your users or the implementation is really off.  I spent lots of time on 
the mailing list talking to developers about various problems and a consistent 
problem was communicating the terminology to users.  Simple things like how do 
you set up your physical disk was not documented well enough to be useful.

the GUI tools did not lead you to a correct solution.  It was just a bunch of 
menu items that you could choose a random.  Hell, tinyca does a better job at 
guiding you in creating a small certificates hierarchy which is a task of 
similar complexity.

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[gentoo-user] Re: OT: Is EVMS dead?

[Alexander Skwar]

Eric S. Johansson <esj@harvee.org> wrote:

> Dirk Heinrichs wrote:
> 
>>> heap.  It's a classic example of "second system syndrome" as defined by
>>> "the mythical Man month".
>> 
>> Errh, what?
> 
> rtfb  it was published in 1972, is still in print and the first five
> chapters
> are as relevant today as they were when it was first published.  It
> explains why
> software projects fail.  I think it's pretty sad when failings in an
> industry recognized 35 years ago are still happening today.
> 
> Brooks says write one system to throw away because you are going to
> anyway.  The first time you implement, you don't understand the problem
> and you frequently
> leave out functionality or implement things in a clumsy or incorrect way. 
> This next implementation you, in theory, understand the problem and can do
> a better job which leads us to...
> 
> second system syndrome.  when you implement a system for the second time
> you think you have the problem fully understood, add lots of features and
> capabilities and end up with a disaster on your hands because you over
> estimated your capabilities.
> 
> which is really Fred Brooks's way of saying write two system to throw away
> because you're going to anyway.
> 
> a great example of this is Microsoft.  They rarely get anything right
> until the
> third version (implementation).  Other examples are easily found if you
> just look.
> 
>> 
>>> It's overly complicated, poorly documented, and
>>> has a terrible user interface that only a geek would even consider
>>> using.
>> 
>> What's wrong with the excelent user guide on the project's site? Which of
>> the three UIs exactly do you think is horrible?
> 
> could never get the containers nesting right.

What "container nesting"? Oh, you're talking about EVMS? I too never
got the hang of it. I'm perfectly fine with using plain LVM.

> If the instructions on how 
> to use an LVM can't be explained on a postcard, you don't understand how
> to communicate

pvcreate /dev/hda
vgcreate data /dev/hda
lvcreate -L42g data
mkfs /dev/data/lvol0

What's so hard about that? Does that fit on a postcard?

-v:
pvcreate /dev/hda: Intialize the device as a physical volume (pv),
so that it can be used by LVM. One time job.
vgcreate data /dev/hda: Create a container called "data" which will
hold the different sub-containers. The "data" container is made up
of the /dev/hda physical volume.
lvcreate -L42g data: Create a logical volume (lv) on the "data"
volume group (vg). It's sized "42g" (42GiB).
mkfs /dev/data/lvol0: Create a file system on the newly created lv.

> with your users or the implementation is really off.

Nope. Some things simply *ARE* complicated.

Alexander Skwar

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[gentoo-user] Re: OT: Is EVMS dead?

[Alexander Skwar]

Eric S. Johansson <esj@harvee.org> wrote:

> Eric Martin wrote:
> 
>> drive.  All I had to do was vgscan and vgchange -a y and I was up and
>> running.  Actually, I too had a problem with my VG's named the same
>> thing.  It wasn't a problem to access different LV's but I changed the
>> VG anyway.  As a pointer for people, you might want to append the name
>> of your box to your VG, that way it will be (probably) unique on your
>> network.  Also you'll know where you are if you need to do a backup
>> like I had to.
> 
> that's a really good suggestion (appending the system name).  As for the
> just
> doing a VGA scan etc., never work for me.

What "VGA scan"?

> Usually the drive would not be 
> recognized and as far as the new system is concerned, the only useful
> thing you could do with it was format.

WFM. You must be doing something strange.

Alexander Skwar

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Re: [gentoo-user] Re: OT: Is EVMS dead?

[Eric S. Johansson]

Alexander Skwar wrote:
> Eric S. Johansson <esj@harvee.org> wrote:
> 
>> Dirk Heinrichs wrote:
>> 
>>>> heap.  It's a classic example of "second system syndrome" as defined by
>>>>  "the mythical Man month".
>>> Errh, what?
>> rtfb  it was published in 1972, is still in print and the first five 
>> chapters are as relevant today as they were when it was first published.
>> It explains why software projects fail.  I think it's pretty sad when
>> failings in an industry recognized 35 years ago are still happening today.
>> 
>> Brooks says write one system to throw away because you are going to anyway.
>> The first time you implement, you don't understand the problem and you
>> frequently leave out functionality or implement things in a clumsy or
>> incorrect way. This next implementation you, in theory, understand the
>> problem and can do a better job which leads us to...
>> 
>> second system syndrome.  when you implement a system for the second time 
>> you think you have the problem fully understood, add lots of features and 
>> capabilities and end up with a disaster on your hands because you over 
>> estimated your capabilities.
>> 
>> which is really Fred Brooks's way of saying write two system to throw away 
>> because you're going to anyway.
>> 
>> a great example of this is Microsoft.  They rarely get anything right until
>> the third version (implementation).  Other examples are easily found if you
>>  just look.
>> 
>>>> It's overly complicated, poorly documented, and has a terrible user
>>>> interface that only a geek would even consider using.
>>> What's wrong with the excelent user guide on the project's site? Which of
>>>  the three UIs exactly do you think is horrible?
>> could never get the containers nesting right.
> 
> What "container nesting"? Oh, you're talking about EVMS? I too never got the
> hang of it. I'm perfectly fine with using plain LVM.
> 
>> If the instructions on how to use an LVM can't be explained on a postcard,
>> you don't understand how to communicate
> 
> pvcreate /dev/hda vgcreate data /dev/hda lvcreate -L42g data mkfs
> /dev/data/lvol0
> 
> What's so hard about that? Does that fit on a postcard?

  it needs a little more detail so a user can extrapolate to what they need but,
yeah that's basically what I'm looking for.  I guess it's time to start the
postcard series of documentation.  :-)

What is hard however is developing the postcard level documentation for disaster
recovery.  Again, that's something I'll work on when I have the time.
> 
> -v: pvcreate /dev/hda: Intialize the device as a physical volume (pv), so
> that it can be used by LVM. One time job.

would need reference physical volume, physical device associations (i.e. single
disc or hardware raid).  is there any way to display/enumerate them independent
of non-LVM devices?  (note: don't need an answer on this, it's just illustrating
the kind of follow-on questions that come up.)

> vgcreate data /dev/hda: Create a container called "data" which will hold the
> different sub-containers. The "data" container is made up of the /dev/hda
> physical volume.

what is a sub container? why is it needed? when do you need it?  do/can you
create a container spanning multiple devices?  When, how, why?

> lvcreate -L42g data: Create a logical volume (lv) on the "data" volume group
> (vg). It's sized "42g" (42GiB).

again, is a logical volume a single physical volume?  If the volume group called
data (how did it get from container to volume group) is the same as the physical
volume, why not just use the physical volume?

> mkfs /dev/data/lvol0: Create a file system on the newly created lv.

in other words, the logical volume is  treated by the system in exactly the same
way as a physical volume.  It's a logical disk.

these are just some of the "naïve user" questions that come to mind.  They
aren't answers concisely in most of the documentation I have seen.  Part of the
reason I say "explain it on a postcard" is because the format forces you to
focus your thoughts and explain the system concisely.  the same technique as
used in communicating with the busy suit although it's usually explaining your
idea in 13 words or less.

> 
>> with your users or the implementation is really off.
> 
> Nope. Some things simply *ARE* complicated.

Richard Feynman, a great physicist, once stated that if you can not explain a
(physics) problem at a freshman level then you don't understand the problem.
Edward Tufte has a series of books on information design simplifying
complicated things so that you can communicate clearly.  Either of these men are
smarter than you and I put together.  I highly recommend reading Tufte's books 
or watch Feynman's testimony at the Challenger committee hearing where he shows 
with a glass of ice water the most likely explanation for the disaster.  Clear, 
simple and easily understood by most people.  If these men successfully 
live/lived by the guideline that complex explanations means you don't 
understand, I'm willing to accept it as true to make that one of my guiding 
principles.


-- 
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Re: [gentoo-user] Re: OT: Is EVMS dead?

[Eric S. Johansson]

Alexander Skwar wrote:
> Eric S. Johansson <esj@harvee.org> wrote:
> What "VGA scan"?

sorry, speech recognition error.
> 
> WFM. You must be doing something strange.

no, I'm what speech recognition researchers call a goat.  I take your bright 
shiny toys, and just by holding them in my hands, you can watch them crumble 
into shit.   it's a talent and a curse.

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Re: [gentoo-user] Re: OT: Is EVMS dead?

[Albert Hopkins]

Most f the questions you have asked are really "LVM 101" type questions
(not any particular implementation of LVM, but LVM in general).  So yes,
to use LVM/EVMS/whatever you sort of have to understand the underlying
principle of what/why.  There's a basic explanation at Wikipedia:
http://en.wikipedia.org/wiki/Logical_volume_management

No, it doesn't fit on a postcard.

> > 
> > Nope. Some things simply *ARE* complicated.
> 
> Richard Feynman, a great physicist, once stated that if you can not explain a
> (physics) problem at a freshman level then you don't understand the problem.
> Edward Tufte has a series of books on information design simplifying
> complicated things so that you can communicate clearly.  Either of these men are
> smarter than you and I put together.  I highly recommend reading Tufte's books 
> or watch Feynman's testimony at the Challenger committee hearing where he shows 
> with a glass of ice water the most likely explanation for the disaster.  Clear, 
> simple and easily understood by most people.  If these men successfully 
> live/lived by the guideline that complex explanations means you don't 
> understand, I'm willing to accept it as true to make that one of my guiding 
> principles.

Often simplifications lead to inaccuracies, misinterpretations, and
confusion.  I'm sure Tufte could have compressed his series of books to
a series of postcards as well.

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[gentoo-user] Re: Re: OT: Is EVMS dead?

[Alexander Skwar]

Eric S. Johansson <esj@harvee.org> wrote:
> Alexander Skwar wrote:
>> Eric S. Johansson <esj@harvee.org> wrote:
>>> Dirk Heinrichs wrote:

>> pvcreate /dev/hda vgcreate data /dev/hda lvcreate -L42g data mkfs
>> /dev/data/lvol0
>> 
>> What's so hard about that? Does that fit on a postcard?
> 
>   it needs a little more detail so a user can extrapolate to what they
>   need but,

The detail can be found in the howto; eg. http://tldp.org/HOWTO/LVM-HOWTO/index.html

> What is hard however is developing the postcard level documentation for
> disaster
> recovery.  

- Get new drive
- Do as mentioned above
- Get stuff from backup

Pretty short, if you ask me ;)

>> -v: pvcreate /dev/hda: Intialize the device as a physical volume (pv), so
>> that it can be used by LVM. One time job.
> 
> would need reference physical volume, physical device associations (i.e.
> single
> disc or hardware raid).

What?

> is there any way to display/enumerate them 
> independent
> of non-LVM devices?

Pardon?

>> vgcreate data /dev/hda: Create a container called "data" which will hold
>> the different sub-containers. The "data" container is made up of the
>> /dev/hda physical volume.
> 
> what is a sub container? 

Exactly.

> why is it needed? when do you need it?  

That's too basic. People asking that kind of question shouldn't be
administering a system.

> do/can  
> you
> create a container spanning multiple devices?  When, how, why?

See howto.

>> lvcreate -L42g data: Create a logical volume (lv) on the "data" volume
>> group (vg). It's sized "42g" (42GiB).
> 
> again, is a logical volume a single physical volume?

They don't belong together. See the howto.

> If the volume group 
> called data (how did it get from container to volume group) 

What?

> is the same as 
> the physical volume,

It isn't. As explained in the howto.

> why not just use the physical volume?  

What?

>> mkfs /dev/data/lvol0: Create a file system on the newly created lv.
> 
> in other words, the logical volume is  treated by the system in exactly
> the same
> way as a physical volume.

Nope.

> It's a logical disk. 

What?

> these are just some of the "naïve user" questions that come to mind. 

Those users shouldn't admin a system.

> They 
> aren't answers concisely in most of the documentation I have seen.  Part
> of the reason I say "explain it on a postcard" is because the format
> forces you to
> focus your thoughts and explain the system concisely.

And those useless questions are because you wanted a postcard explanation.

>>> with your users or the implementation is really off.
>> 
>> Nope. Some things simply *ARE* complicated.
> 
> Richard Feynman, a great physicist, once stated that if you can not
> explain a (physics) problem at a freshman level then you don't understand
> the problem. 

Might be. But you need to have more space than a postcard.

> Edward Tufte has a series of books on information design 
> simplifying
> complicated things so that you can communicate clearly.  Either of these
> men are
> smarter than you and I put together. 

That's not hard (well, at least as far as being smarter than me is
concerned *G*).

Alexander Skwar

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Re: [gentoo-user] Re: Re: OT: Is EVMS dead?

[felix]

On Thu, Nov 08, 2007 at 11:48:11AM +0100, Alexander Skwar wrote:
> Pretty short, if you ask me ;)
> What?
> Pardon?
> Exactly.
> That's too basic. People asking that kind of question shouldn't be
> administering a system.
> See howto.
> They don't belong together. See the howto.
> What?
> It isn't. As explained in the howto.
> What?
> Nope.
> What?
> Those users shouldn't admin a system.
> And those useless questions are because you wanted a postcard explanation.

:-)  Nice postcard answers for a postcard brain.  Some people refuse
to learn anything on their own and want the world to hand it to them
on a platter, err, postcard.  I like the way you did just what he
asked for and it turned out it wasn't what he wanted.

-- 
            ... _._. ._ ._. . _._. ._. ___ .__ ._. . .__. ._ .. ._.
     Felix Finch: scarecrow repairman & rocket surgeon / felix@crowfix.com
  GPG = E987 4493 C860 246C 3B1E  6477 7838 76E9 182E 8151 ITAR license #4933
I've found a solution to Fermat's Last Theorem but I see I've run out of room o
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Re: [gentoo-user] Re: Re: OT: Is EVMS dead?

[Eric Martin]

felix@crowfix.com wrote:
> On Thu, Nov 08, 2007 at 11:48:11AM +0100, Alexander Skwar wrote:
>   
>> Pretty short, if you ask me ;)
>> What?
>> Pardon?
>> Exactly.
>> That's too basic. People asking that kind of question shouldn't be
>> administering a system.
>> See howto.
>> They don't belong together. See the howto.
>> What?
>> It isn't. As explained in the howto.
>> What?
>> Nope.
>> What?
>> Those users shouldn't admin a system.
>> And those useless questions are because you wanted a postcard explanation.
>>     
>
> :-)  Nice postcard answers for a postcard brain.  Some people refuse
> to learn anything on their own and want the world to hand it to them
> on a platter, err, postcard.  I like the way you did just what he
> asked for and it turned out it wasn't what he wanted.
>
>   
"Any philosophy that can be put in a nutshell belongs there."   --
 *Sydney J. Harris*
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Re: [gentoo-user] OT: Is EVMS dead?

[Adam Hamsik]

On Nov,Tuesday 6 2007, at 3:07 AM, Albert Hopkins wrote:

>
> On Mon, 2007-11-05 at 18:01 -0500, Eric S. Johansson wrote:
>
>>
>> given that I frequently play the role of the heretic (complete with  
>> burn scars
>> all over my body and various bits of damage from the weapons of  
>> true believers)
>> I think it's a good thing that EVMS is slated for the trash heap.   
>> It's a
>> classic example of "second system syndrome" as defined by "the  
>> mythical Man
>> month".  It's overly complicated, poorly documented, and has a  
>> terrible user
>> interface that only a geek would even consider using.
>>
>> Having said that, I also think LVMS suffers from many if not all of  
>> the same
>> problems that plagued EVMS.  it is been around for years and still  
>> the
>> documentation on how to perform common operations is lacking.  It's  
>> a chicken
>> and egg problem.  You need to understand LVMS in order to  
>> understand the
>> documentation and then you can't explain it to anyone else.  Every  
>> time I've
>> used LVMS, it takes me the same number of hours to relearn the same  
>> old pieces
>> of obscure command syntax and become comfortable that I'm not going  
>> to trash my
>> disk.  As a result, I don't use LVMS either.
>>
> I've never used EVMS so I can't comment at all on it.  However I have
> been using LVM for years and one of the few good things I can say  
> about
> it is that its pretty small, easy, and predictable. In fact one of the
> negative things I'd have to say about it is that it's *too* simple  
> (a LV
> defrag tool would be nice).  I really don't understand the complexity
> you speak of.  It's pretty well documented, and has a fairly high
> user-base.
>
> I do agree though that, based on this ML and IRC discussions, many  
> times
> I'll see a person who wants to use LVM and perhaps maybe they don't  
> need
> it, and they get frustrated because they're using the wrong tool for  
> the
> job.  Myself: I have a 8 2-disk RAID volumes with LVM on top.  If I  
> need
> to expand my VG, I just pop in a couple of new drives, to an  
> lvextend on
> a volume and then "mount -o remount,resize" and voila!
>
> On another machine I have xen and I have 2 VGs: a set of disks for the
> Host and a set for the VMs.  I have some VMs in a DMZ, and I can't  
> reach
> them from the host, but I use LVM to create snapshots of their disks  
> and
> make backup of them.  LVM makes it damn easy. In some ways LVM is  
> like a
> poor-man's SAN for Xen VMs.  You can carve out a LV, assign it to a  
> VM,
> and resize, hot-add or hot-remove them as you please.
>
> But again, the average person with a single disk running on a laptop
> computer probably has no use for LVM.
>
> Pretty much every major "server" OS has volume management (including
> Windows) because a lot of users at that level need it.  Linu LVM, I
> think, is very similar to HP-UX LVM at the command level.
AFAIK an who has written linux LVM worked for HP.

Regards

Adam.

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