From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Navin P.S" <navinp1912@gmail.com>
Subject: write directly to device mapper snapshot origin device ?
Date: Thu, 14 Jul 2016 19:55:25 +0530
Message-ID: <CAA=4086wdhAxNsWjAYgZG3bWORV2vF3YpMQk9OTjAg22MJi07Q@mail.gmail.com>
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Hi,
  Can i do dd if=/dev/zero of=/dev/mapper/dmo count=20 ? where dmo is
a dm snapshot origin created through dmsetup command. Instead of
/dev/zero i can write valid devices.

I could create the dmo through some lvm2 commands. Is direct write
with 4k (page size values ) allowed when it is mapped to 2 block
devices in linear mode ?


Regards,
-- Navin