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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>I do not understand why creating a linear device and then trying to create another linear device on top of it fails.<br><br><o:p></o:p></p><p class=MsoListParagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:0cm;margin-left:36.0pt;margin-bottom:.0001pt;text-align:left;text-indent:-18.0pt;mso-list:l0 level1 lfo2;direction:ltr;unicode-bidi:embed'><![if !supportLists]><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span dir=LTR></span>Creating a linear device over loop1:<br>===========================<br>dmsetup create linear_loop1 /tmp/linear_loop1<br><br>cat /tmp/linear_loop1<br>0 1000 linear /dev/loop1 0<br><br><o:p></o:p></p><p class=MsoListParagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:0cm;margin-left:36.0pt;margin-bottom:.0001pt;text-align:left;text-indent:-18.0pt;mso-list:l0 level1 lfo2;direction:ltr;unicode-bidi:embed'><![if !supportLists]><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span dir=LTR></span>Then creating another linear device over this linear device:<br>=============================================<br>dmsetup create linear_loop2 /tmp/linear_loop2<br><br>device-mapper: reload ioctl failed: Invalid argument<br>Command failed<br><br>cat /tmp/klinear_loop2<br>0 1000 linear /dev/linear_loop1 0<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Could you please explain what am I doing wrong?<o:p></o:p></p></div></body></html>