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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Yes, it’s possible. We do it. I can’t share the code, but I can describe it.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We create a master container using standard lxc-create script with our own template and config file. The template is based on the ubuntu template. The master container is never started. All subsequent containers share the rootfs of the master container.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We use the lxc library to read the master container’s config, then fork and call lxc_start to run a program in a new container using the config we read. But, you should be able to do this with scripts, if that is your choice.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>A couple of warnings. You need to create an empty directory in /var/lib/lxc for each container that matches the name specified in the lxc_start call. You must create the containers serially. This technique will fail if lxc-create is called concurrently by different threads or processes.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We are using Ubuntu 12.04 LTS 64-bit.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Regards.</span><span style='color:#1F497D'><br></span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Mark K Vallevand <a href="mailto:Mark.Vallevand@Unisys.com"><span style='color:blue'>Mark.Vallevand@Unisys.com</span></a></span><span style='color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>May you live in interesting times, may you come to the attention of important people and may all your wishes come true.<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:10.0pt;color:#1F497D'>THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY MATERIAL and is thus for use only by the intended recipient. If you received this in error, please contact the sender and delete the e-mail and its attachments from all computers.</span><span style='color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Ajith Adapa [mailto:ajith.adapa@gmail.com] <br><b>Sent:</b> Monday, July 08, 2013 11:23 PM<br><b>To:</b> Lxc-users@lists.sourceforge.net<br><b>Subject:</b> [Lxc-users] Using common rootfs for multiple containers<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><div><div><div><p class=MsoNormal style='margin-bottom:12.0pt'>Hi,<o:p></o:p></p></div><p class=MsoNormal style='margin-bottom:12.0pt'>I would like it know is it possible to create a single rootfs (might be in read-only mode) and share it among multiple containers ?<o:p></o:p></p></div><p class=MsoNormal style='margin-bottom:12.0pt'>Currently for every container we create its own unique rootfs.<o:p></o:p></p></div><div><p class=MsoNormal>What would be the best place to look in code for using single rootfs across multiple containers.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>Regards,<o:p></o:p></p></div><p class=MsoNormal>Ajith<o:p></o:p></p></div></div></body></html>