Re: new pc and swap

[Richard Hector]

On 01/11/16 19:04, Johann Spies wrote:
> LVM has bitten me more than once in the past and I will not use it
> again.  In both situations it spanned more than one disk and one of the
> disks failed - leaving you with unrecoverable data.

I don't think I've ever used it like that, and probably wouldn't. At
least not unless the underlying devices were RAID1 or similar.

Spanning devices seems to me to be more or less the same as RAID0
(striping), and just as risky - perhaps slightly more convenient to
recover data from, but it certainly doesn't sound easy.

On the other hand, constraining myself to one 'device' (generally an
mdraid RAID1 device, often on partitions smaller than the disk) per vg,
I would rarely do without it.

Richard




signature.asc
Description: OpenPGP digital signature

Re: terminate unwanted bug mail how?

[Brian]

On Mon 31 Oct 2016 at 21:08:08 -0400, Felix Miata wrote:

> Brian composed on 2016-10-31 22:27 (UTC):
> 
> >But we are still in the dark. And it does not appear you have
> >investigated what mailfilter can do if your bandwidth is contrained
> 
> Another mistake. I supposed you meant mail filter rather than an app named
> [M]ailfilter. Now that I'm apprised of mailfilter I will need to
> investigate, once I've encountered of an available round tuit. It sounds
> like something overdue for many moons.

mailfilter deletes mail on the server. One criterion is size, which can
be set to a threshhold.

-- 
Brian.

Re: new pc and swap

[Pascal Hambourg]

Le 01/11/2016 à 09:25, Richard Hector a écrit :

On 01/11/16 19:04, Johann Spies wrote:

LVM has bitten me more than once in the past and I will not use it
again.  In both situations it spanned more than one disk and one of the
disks failed - leaving you with unrecoverable data.


I don't think I've ever used it like that, and probably wouldn't. At
least not unless the underlying devices were RAID1 or similar.


Indeed it is highly recommended to use some redundancy (external with 
physical or software mdadm RAID, or internal within LVM) when spanning 
LVM over multiple disks.



Spanning devices seems to me to be more or less the same as RAID0
(striping), and just as risky


The default is to concatenate PVs like RAID "linear" (JBOD), although 
LVM can do striping too.

Re: Alternative to Adobe Reader, anyone?

[Brian]

On Mon 31 Oct 2016 at 23:38:36 +, Lisi Reisz wrote:

> On Monday 31 October 2016 20:34:32 Brian wrote:
> > I _do_
> >
> > > get offered the chance to switch landscape to portrait.
> >
> > You final sentence is what interests me.
> >
> > What would expect to happen if you chose "portrait" over "landscape"?
> >
> > Bear in mind most printers feed paper in short-edge first.
> 
> Portrait is the default.  If I do not ask it to turn a landscape image round, 
> a high percentage of it will be outside the printing area and I would have 
> tramlines at the top and bottom of the page.
> 
> Put a landscape image over the top of a portrait oriented sheet of paper and 
> you'll see what I mean.

I understand what you mean. If we are still talking in the context of
Evince, the "Landscape" and "Portrait" options are handled by Cairo, not
CUPS. If you select "Landscape", Cairo rotates *every" page in the PDF
by 90 degrees if the page width is *less* than the height. If you had a
842x595 sized pages they would not be rotated. Effectively, the option
does nothing. Or rather - it doesn't do what you think it does.

But (you say). the printout is OK. That's because you have the "Auto
Rotate and Centre" option ticked. Nothing to do with "Landscape"
selected.

Even if you forgot to tick "Auto Rotate and Centre" and sent a 842x595
page to the printer it will still be printed correctly because the
pdftopdf filter of cups-filters automatically rotates landscape pages by
90 degrees before printing.

-- 
Brian.

Re: new pc and swap

[Stefan Monnier]

>> LVM has bitten me more than once in the past and I will not use it
>> again.  In both situations it spanned more than one disk and one of the
>> disks failed - leaving you with unrecoverable data.
> I don't think I've ever used it like that, and probably wouldn't. At
> least not unless the underlying devices were RAID1 or similar.

The only times I put several PVs in a VG is when moving data between
disks:
- pvcreate /dev/sd
- vgextend  /dev/sd
- pvmove /dev/sd
- vgreduce  /dev/sd

But indeed, this creates a temporary mirror and is hence safe w.r.t
disk failure.


Stefan

how to turn off backlight in console (without any X server)

[Laurent Debian]

Hi all,

I would like to turn off the backlight completly on a  mac book pro 2008
(sid).
I don't have any x server.  Does it explains this error ?

>  xbacklight -set 10
> RANDR Query Version returned error -1
>

the graphic card is
02:00.0 VGA compatible controller: NVIDIA Corporation C79 [GeForce 9400M]
(rev b1)
nouveau is loaded by the kernel.

Any way to turn off the backlight without installing  X woudl be greatly
appreciated.

Cheers,
Laurent.

Re: how to turn off backlight in console (without any X server)

[tomas]

-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

On Tue, Nov 01, 2016 at 02:22:46PM +0100, Laurent Debian wrote:
> Hi all,
> 
> I would like to turn off the backlight completly on a  mac book pro 2008
> (sid).
> I don't have any x server.  Does it explains this error ?

Most probably yes. "Xbacklight" hints at an X application. RandR is an
X server extension.

> >  xbacklight -set 10
> > RANDR Query Version returned error -1
> >
> 
> the graphic card is
> 02:00.0 VGA compatible controller: NVIDIA Corporation C79 [GeForce 9400M]
> (rev b1)
> nouveau is loaded by the kernel.

I'd imagine that xbacklight (and xrandr) try to talk to the X server to
do their bidding.

> 
> Any way to turn off the backlight without installing  X woudl be greatly
> appreciated.

Have a look at the files under /sys/class/backlight. For me, this works:

  sudo bash -c "echo 2 > /sys/class/backlight/acpi_video0/brightness"

Enjoy

- -- t
-BEGIN PGP SIGNATURE-
Version: GnuPG v1.4.12 (GNU/Linux)

iEYEARECAAYFAlgYnW0ACgkQBcgs9XrR2kb+vQCfaJwwyrg9ZpPdlmLpYkQwhpJ2
fS8An1rsuKp8O8dq3X0NwjKP1mMGS37w
=LcrE
-END PGP SIGNATURE-

Re: new pc and swap

[Pascal Hambourg]

Le 01/11/2016 à 14:07, Stefan Monnier a écrit :


The only times I put several PVs in a VG is when moving data between
disks:


Several PVs does not mean several disks.

A use case of multiple PVs per VG on one disk is when you want to create 
several VGs (for whatever reason) and be able to extend them. So you 
leave free space on the disk and create a new PV every time you need to 
extend a VG.

Re: Alternative to Adobe Reader, anyone?

[Lisi Reisz]

On Tuesday 01 November 2016 10:30:54 Brian wrote:
> On Mon 31 Oct 2016 at 23:38:36 +, Lisi Reisz wrote:
> > On Monday 31 October 2016 20:34:32 Brian wrote:
> > > I _do_
> > >
> > > > get offered the chance to switch landscape to portrait.
> > >
> > > You final sentence is what interests me.
> > >
> > > What would expect to happen if you chose "portrait" over "landscape"?
> > >
> > > Bear in mind most printers feed paper in short-edge first.
> >
> > Portrait is the default.  If I do not ask it to turn a landscape image
> > round, a high percentage of it will be outside the printing area and I
> > would have tramlines at the top and bottom of the page.
> >
> > Put a landscape image over the top of a portrait oriented sheet of paper
> > and you'll see what I mean.
>
> I understand what you mean. If we are still talking in the context of
> Evince, the "Landscape" and "Portrait" options are handled by Cairo, not
> CUPS. If you select "Landscape", Cairo rotates *every" page in the PDF
> by 90 degrees if the page width is *less* than the height. If you had a
> 842x595 sized pages they would not be rotated. Effectively, the option
> does nothing. Or rather - it doesn't do what you think it does.
>
> But (you say). the printout is OK. That's because you have the "Auto
> Rotate and Centre" option ticked. Nothing to do with "Landscape"
> selected.
>
> Even if you forgot to tick "Auto Rotate and Centre" and sent a 842x595
> page to the printer it will still be printed correctly because the
> pdftopdf filter of cups-filters automatically rotates landscape pages by
> 90 degrees before printing.

It must be my printer that is doing it then.  I agree that if the image will 
fit I am asked nothing.  But if I have a landscape A4 image I am asked if I 
want it rotated to portrait.

My current Evince has gone mad anyway and I have not yet battled it.  I am just 
using kpdf-trinity most of the time.  I rarely need to do more to a pdf than 
read it.  I can't check what the default ticks in Evince are because I can't 
currently get at any of the settings.  I have altered nothing in it.  I can't 
get at it!!

Lisi

Re: Alternative to Adobe Reader, anyone?

[Brian]

On Tue 01 Nov 2016 at 14:56:04 +, Lisi Reisz wrote:

> On Tuesday 01 November 2016 10:30:54 Brian wrote:
> > On Mon 31 Oct 2016 at 23:38:36 +, Lisi Reisz wrote:
> > > On Monday 31 October 2016 20:34:32 Brian wrote:
> > > > I _do_
> > > >
> > > > > get offered the chance to switch landscape to portrait.
> > > >
> > > > You final sentence is what interests me.
> > > >
> > > > What would expect to happen if you chose "portrait" over "landscape"?
> > > >
> > > > Bear in mind most printers feed paper in short-edge first.
> > >
> > > Portrait is the default.  If I do not ask it to turn a landscape image
> > > round, a high percentage of it will be outside the printing area and I
> > > would have tramlines at the top and bottom of the page.
> > >
> > > Put a landscape image over the top of a portrait oriented sheet of paper
> > > and you'll see what I mean.
> >
> > I understand what you mean. If we are still talking in the context of
> > Evince, the "Landscape" and "Portrait" options are handled by Cairo, not
> > CUPS. If you select "Landscape", Cairo rotates *every" page in the PDF
> > by 90 degrees if the page width is *less* than the height. If you had a
> > 842x595 sized pages they would not be rotated. Effectively, the option
> > does nothing. Or rather - it doesn't do what you think it does.
> >
> > But (you say). the printout is OK. That's because you have the "Auto
> > Rotate and Centre" option ticked. Nothing to do with "Landscape"
> > selected.
> >
> > Even if you forgot to tick "Auto Rotate and Centre" and sent a 842x595
> > page to the printer it will still be printed correctly because the
> > pdftopdf filter of cups-filters automatically rotates landscape pages by
> > 90 degrees before printing.
> 
> It must be my printer that is doing it then.  I agree that if the
> image will fit I am asked nothing.  But if I have a landscape A4 image
> I am asked if I want it rotated to portrait.

It would be highly unusual for your printer itself to do rotation of a
page sent to it. I've only ever seen it being done by the sending
application or by CUPS/cups-filters. If you are being asked then that
would surely be a question from the sending software. With Jessie it
would be a redundant question because pdftopdf will automatically rotate
it anyway.

> My current Evince has gone mad anyway and I have not yet battled it.
> I am just using kpdf-trinity most of the time.  I rarely need to do
> more to a pdf than read it.  I can't check what the default ticks in
> Evince are because I can't currently get at any of the settings.  I
> have altered nothing in it.  I can't get at it!!

I'm unfamiliar with kpdf but autorotation should happen if the CUPS
version is 1.7. A solution to your Evince problem could be purging and
reinstalling it.

-- 
Brian.

Re: terminate unwanted bug mail how?

[Gene Heskett]

On Tuesday 01 November 2016 05:45:39 Brian wrote:

> On Mon 31 Oct 2016 at 21:08:08 -0400, Felix Miata wrote:
> > Brian composed on 2016-10-31 22:27 (UTC):
> > >But we are still in the dark. And it does not appear you have
> > >investigated what mailfilter can do if your bandwidth is contrained
> >
> > Another mistake. I supposed you meant mail filter rather than an app
> > named [M]ailfilter. Now that I'm apprised of mailfilter I will need
> > to investigate, once I've encountered of an available round tuit. It
> > sounds like something overdue for many moons.
>
> mailfilter deletes mail on the server. One criterion is size, which
> can be set to a threshhold.

No, it doesn't IF your server is shentel.net.  When I called to complain, 
they explained that many people use pop3, but expected the message to 
still be there when accessed by imap. So I am forced to login to their 
webmail server, and delete old mail that way. Which I am now doing 
nominally daily.

I am all automated pop3 here. But I will say their spam trapping is much 
better than the average. So much so that I have discontinued using 
mailfilter.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

Re: terminate unwanted bug mail how?

[Brian]

On Tue 01 Nov 2016 at 11:52:50 -0400, Gene Heskett wrote:

> On Tuesday 01 November 2016 05:45:39 Brian wrote:
> 
> > On Mon 31 Oct 2016 at 21:08:08 -0400, Felix Miata wrote:
> > > Brian composed on 2016-10-31 22:27 (UTC):
> > > >But we are still in the dark. And it does not appear you have
> > > >investigated what mailfilter can do if your bandwidth is contrained
> > >
> > > Another mistake. I supposed you meant mail filter rather than an app
> > > named [M]ailfilter. Now that I'm apprised of mailfilter I will need
> > > to investigate, once I've encountered of an available round tuit. It
> > > sounds like something overdue for many moons.
> >
> > mailfilter deletes mail on the server. One criterion is size, which
> > can be set to a threshhold.
> 
> No, it doesn't IF your server is shentel.net.  When I called to complain, 
> they explained that many people use pop3, but expected the message to 
> still be there when accessed by imap. So I am forced to login to their 
> webmail server, and delete old mail that way. Which I am now doing 
> nominally daily.

That is partly why I invited the OP to say a little something about how
he got mail.

> I am all automated pop3 here. But I will say their spam trapping is much 
> better than the average. So much so that I have discontinued using 
> mailfilter.

IPS's filtering can go awry. I prefer to make my own mistakes. The
person responsible is close at hand and can be re-educated.

-- 
Brian.

Re: new pc and swap

[Ben Caradoc-Davies]

On 01/11/16 19:04, Johann Spies wrote:

LVM has bitten me more than once in the past and I will not use it again.
In both situations it spanned more than one disk and one of the disks
failed - leaving you with unrecoverable data.


I use LVM inside LUKS on a single device. This configuration is great 
for requiring only one encrypted partition, with LVM providing the 
benefit of multiple logical volumes and the management benefits of 
separate volumes for root and home (for example).


Kind regards,

--
Ben Caradoc-Davies 
Director
Transient Software Limited 
New Zealand

Re: new pc and swap

[Richard Hector]

On 01/11/16 22:57, Pascal Hambourg wrote:
>> Spanning devices seems to me to be more or less the same as RAID0
>> (striping), and just as risky
> 
> The default is to concatenate PVs like RAID "linear" (JBOD), although
> LVM can do striping too.

True, but either way, removing one disk may damage a volume.

Richard