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From: "Tomas Dalebjörk" <tomas.dalebjork@gmail.com>
To: Zdenek Kabelac <zkabelac@redhat.com>
Cc: LVM general discussion and development <linux-lvm@redhat.com>
Subject: Re: [linux-lvm] exposing snapshot block device
Date: Mon, 7 Sep 2020 18:34:15 +0200	[thread overview]
Message-ID: <F484D1CA-73F2-49EE-9EE1-1902F322A591@gmail.com> (raw)
In-Reply-To: <a446fda9-d3c5-a184-8466-d63ae39f541c@redhat.com>

thanks for feedback 

so if I understand this correctly
# fallocate -l 100M /tmp/pv1
# fallocate -l 100M /tmp/pv2
# fallocate -l 100M /tmp/pv3

# losetup —find —show /tmp/pv1
# losetup —find —show /tmp/pv2
# losetup —find —show /tmp/pv3

# vgcreate vg0 /dev/loop0
# lvcreate -n lv0 -l 1 vg0
# vgextend vg0 /dev/loop1
# lvcreate -s -l 1 -n lvsnap /dev/loop1
# vgchange -a n vg0

# lvconvert —splitsnapshot vg0/lvsnap

# vgreduce vg0 /dev/loop1

# vgcreate vg1 /dev/loop2
# lvcreate -n lv0 -l 1 vg1
# vgextend vg1 /dev/loop1 
# lvconvert -s vg1/lvsnap vg1/lv0

not sure if the steps are correct?

regards Tomas

Sent from my iPhone

> On 7 Sep 2020, at 16:17, Zdenek Kabelac <zkabelac@redhat.com> wrote:
> 
> Dne 07. 09. 20 v 16:14 Dalebjörk, Tomas napsal(a):
>> Hi Mikulas,
>> Thanks for the replies
>> I am confused now with the last message?
>> LVM doesn't support taking existing cow device and attaching it to an existing volume?
>> Isn't that what "lvconvert --splitsnapshot" & "lvconvert -s" is ment to be doing?
>> lets say that I create the snapshot on a different device using these steps:
>> root@src# lvcreate -s -L 10GB -n lvsnap vg/lv /dev/sdh
>> root@src# lvconvert ---splitsnapshot vg/lvsnap
>> root@src# echo "I now move /dev/sdb to another server"
>> root@tgt# lvconvert -s newvg/newlv vg/lvsnap
> 
> Hi
> 
> This is only supported as long as you stay within VG.
> So newlv & lvsnap must be in a single VG.
> 
> Note - you can 'vgreduce' PV from VG1 and vgextend to VG2.
> But it always work on whole PV base - you can't mix
> LV between VGs.
> 
> Zdenek
> 

  reply	other threads:[~2020-09-07 16:34 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-22 10:47 [linux-lvm] exposing snapshot block device Dalebjörk, Tomas
2019-10-22 13:57 ` Zdenek Kabelac
2019-10-22 15:29   ` Dalebjörk, Tomas
2019-10-22 15:36     ` Zdenek Kabelac
2019-10-22 16:13       ` Dalebjörk, Tomas
2019-10-23 10:26         ` Zdenek Kabelac
2019-10-23 10:56           ` Tomas Dalebjörk
2019-10-22 16:15       ` Stuart D. Gathman
2019-10-22 17:02         ` Tomas Dalebjörk
2019-10-22 21:38         ` Gionatan Danti
2019-10-22 22:53           ` Stuart D. Gathman
2019-10-23  6:58             ` Gionatan Danti
2019-10-23 10:06               ` Tomas Dalebjörk
2019-10-23 10:12             ` Zdenek Kabelac
2019-10-23 10:46         ` Zdenek Kabelac
2019-10-23 11:08           ` Gionatan Danti
2019-10-23 11:24             ` Tomas Dalebjörk
2019-10-23 11:26               ` Tomas Dalebjörk
2019-10-24 16:01               ` Zdenek Kabelac
2019-10-25 16:31                 ` Tomas Dalebjörk
2019-11-04  5:54                   ` Tomas Dalebjörk
2019-11-04 10:07                     ` Zdenek Kabelac
2019-11-04 14:40                       ` Tomas Dalebjörk
2019-11-04 15:04                         ` Zdenek Kabelac
2019-11-04 17:28                           ` Tomas Dalebjörk
2019-11-05 16:24                             ` Zdenek Kabelac
2019-11-05 16:40                         ` Mikulas Patocka
2019-11-05 20:56                           ` Tomas Dalebjörk
2019-11-06  9:22                             ` Zdenek Kabelac
2019-11-07 16:54                             ` Mikulas Patocka
2019-11-07 17:29                               ` Tomas Dalebjörk
2020-09-04 12:09                                 ` Tomas Dalebjörk
2020-09-04 12:37                                   ` Zdenek Kabelac
2020-09-07 13:09                                   ` Mikulas Patocka
2020-09-07 14:14                                     ` Dalebjörk, Tomas
2020-09-07 14:17                                       ` Zdenek Kabelac
2020-09-07 16:34                                         ` Tomas Dalebjörk [this message]
2020-09-07 16:42                                           ` Zdenek Kabelac
2020-09-07 17:37                                             ` Tomas Dalebjörk
2020-09-07 17:50                                               ` Zdenek Kabelac
2020-09-08 12:32                                                 ` Dalebjörk, Tomas
2020-09-07 19:56                                             ` Tomas Dalebjörk
2020-09-07 20:22                                               ` Tomas Dalebjörk
2020-09-07 21:02                                               ` Tomas Dalebjörk
2019-10-23 12:12             ` Ilia Zykov
2019-10-23 12:20             ` Ilia Zykov
2019-10-23 13:05               ` Zdenek Kabelac
2019-10-23 14:40                 ` Gionatan Danti
2019-10-23 15:46                   ` Ilia Zykov
2019-10-23 12:59             ` Zdenek Kabelac
2019-10-23 14:37               ` Gionatan Danti
2019-10-23 15:37                 ` Zdenek Kabelac
2019-10-23 17:16                   ` Gionatan Danti

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