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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi all,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have a goal in mind and I'm not entirely sure how to reach it. So… with this in mind, I thought I would discuss what I want as an end result and then ask if a certain approach may make sense.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>End goal: Create a highly available (no single point of failure) scale out infrastructure for booting and running diskless XenServer hosts and lots of Guest Operating systems that have live migration capabilities. I want this with as few systems in place as is possible.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>While most people will start down the iSCSI path, I am not entirely sure that this is the approach I would like to look at. The iPXE full iSCSI stack is awesome and provides great capabilities but it requires a lot of clustering work to make it highly available. This is compounded if you want a cluster with more than 2 nodes.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I am interested in using the ceph clustered storage system. This system already provides me with a highly available scale out solution and… once configured and working give me the highly available storage I want and integrates well with the Xen Clients.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>But… the hard part is that I want to boot diskless XenServers from this ceph store. This is where:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> 1) iPXE comes in<o:p></o:p></p><p class=MsoNormal> 2) My knowledge about ends<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>My thought is that I would boot a customized iPXE from a tiny USB DOM or a highly available DHCP/TFTP/PXEboot infrastructure. Once iPXE is running, I would like to boot directly from a ceph cluster volume instead of the more standard iSCSI volume.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So, I wanted to ask thoughts on whether it makes sense to try to develop another backend connectivity option to iPXE. I would like to look at adding a ceph/RBD option that will allow me to provide a list of IP addresses (and other needed config info) for the ceph cluster and allow me to mount a ceph store to boot from.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Then… I would have to address the problem of how to get an initrd for XenServer that would have the ceph modules available and allow me to boot a root file system from there.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is iPXE the correct place to look to help provide this?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is this a hugely monumental project… or just a monumental project (given that the ceph client code exists and is open source)…<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I thought I would reach out here before I wrote to the ceph group. I my approach is embarrassingly wrong, please feel free to let me know!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>- Steve<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>