From: Roland <devzero@web.de>
To: LVM general discussion and development <linux-lvm@redhat.com>,
Andy Smith <andy@strugglers.net>
Subject: Re: [linux-lvm] convert logical sector -> physical sector + pv/vg extent number
Date: Mon, 3 Jan 2022 17:43:01 +0100 [thread overview]
Message-ID: <e9a7143a-9746-3d01-7543-d55f2df01d9b@web.de> (raw)
In-Reply-To: <a6e37c26-77c4-2a8e-ab81-3a909c477a47@web.de>
> any chance to get retrieve this information for automated/script
based processing ?
after long trial and error and reading manpages, i got it (see below):
what i'm yet missing is how "translation" of the headings/fields in
normal output can be avoided , i.e print the technical/internal field
name instead of a "human readable" or "translated" one.
'seg_start_pe' and 'pvseg_start' for example both translate to "Start",
and that does not only make it hard to read (and makes no real sense to
have duplicate field names) , but it's also difficult to build an
appropriate output field command option from the default output. i
remember i had such issue with other tools...
think this is a missing feature ?
roland
# pvs --segments -olv_name,seg_start_pe,seg_size_pe,pvseg_start -S
lv_name=usedblocks -O seg_start
LV Start SSize Start
usedblocks 0 1 512
usedblocks 1 233 1
usedblocks 234 1 513
usedblocks 235 277 235
# pvs --segments -olv_name,seg_start_pe,seg_size_pe,pvseg_start -S
lv_name=markedbad -O seg_start
LV Start SSize Start
markedbad 0 1 1022
markedbad 1 1 0
markedbad 2 1 234
# pvs --segments -olv_name,seg_start_pe,seg_size_pe,pvseg_start -S
lv_name=markedbad -O seg_start --nameprefixes --noheadings
LVM2_LV_NAME='markedbad' LVM2_SEG_START_PE='0' LVM2_SEG_SIZE_PE='1'
LVM2_PVSEG_START='1022'
LVM2_LV_NAME='markedbad' LVM2_SEG_START_PE='1' LVM2_SEG_SIZE_PE='1'
LVM2_PVSEG_START='0'
LVM2_LV_NAME='markedbad' LVM2_SEG_START_PE='2' LVM2_SEG_SIZE_PE='1'
LVM2_PVSEG_START='234'
# pvs --segments -olv_name,seg_start_pe,seg_size_pe,pvseg_start -S
lv_name=usedblocks -O seg_start --nameprefixes --noheadings
LVM2_LV_NAME='usedblocks' LVM2_SEG_START_PE='0' LVM2_SEG_SIZE_PE='1'
LVM2_PVSEG_START='512'
LVM2_LV_NAME='usedblocks' LVM2_SEG_START_PE='1'
LVM2_SEG_SIZE_PE='233' LVM2_PVSEG_START='1'
LVM2_LV_NAME='usedblocks' LVM2_SEG_START_PE='234'
LVM2_SEG_SIZE_PE='1' LVM2_PVSEG_START='513'
LVM2_LV_NAME='usedblocks' LVM2_SEG_START_PE='235'
LVM2_SEG_SIZE_PE='277' LVM2_PVSEG_START='235'
Am 03.01.22 um 12:13 schrieb Roland:
> thanks!
>
> any chance to get retrieve this information for automated/script based
> processing ?
>
> roland
>
>
> Am 03.01.22 um 00:12 schrieb Andy Smith:
>> Hi Roland,
>>
>> On Sun, Jan 02, 2022 at 08:00:30PM +0100, Roland wrote:
>>> if i have a logical sector/block "x" on a lvm logical volume , is
>>> there
>>> a way to easily calculate/determine (optimally by script/cli) the
>>> corresponding physical sector of the physical device it belongs to and
>>> the extent number of the appropiate pv/vg where it resides ?
>> lvdisplay --maps /path/to/lv
>>
>> tells you all the mappings of logical extents within the LV to
>> physical extents within the PV.
>>
>> pvdisplay --units s /dev/yourpv | grep 'PE Size'
>>
>> tells you the size of a physical extent in sectors.
>>
>> Between those you can work out the sector number on the physical
>> device for a sector number on a logical volume.
>>
>> Cheers,
>> Andy
>>
>> _______________________________________________
>> linux-lvm mailing list
>> linux-lvm@redhat.com
>> https://listman.redhat.com/mailman/listinfo/linux-lvm
>> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
>>
_______________________________________________
linux-lvm mailing list
linux-lvm@redhat.com
https://listman.redhat.com/mailman/listinfo/linux-lvm
read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
next prev parent reply other threads:[~2022-01-03 16:43 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-02 19:00 [linux-lvm] convert logical sector -> physical sector + pv/vg extent number Roland
2022-01-02 23:12 ` Andy Smith
2022-01-03 11:13 ` Roland
2022-01-03 16:43 ` Roland [this message]
2022-01-06 13:47 ` Stuart D Gathman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=e9a7143a-9746-3d01-7543-d55f2df01d9b@web.de \
--to=devzero@web.de \
--cc=andy@strugglers.net \
--cc=linux-lvm@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).