Regards, Sateesh
> -----Original Message----- > From: Sateesh Chodapuneedi [mailto:sateesh.chodapune...@citrix.com] > Sent: 17 February 2014 10:18 > To: dev@cloudstack.apache.org > Subject: [PROPOSAL] Granular Controller Support in CloudStack over VMware > deployments > > Hi, > > I would like to add support for granular disk controller support for > CloudStack over VMware deployments. > > To access virtual disks, CD/DVD-ROM, and SCSI devices, a virtual machine uses > storage controllers. > > Virtual storage controllers appear to a virtual machine as different types of > controllers of type IDE or SCSI. Further SCSI controllers can be > classified into 4 sub types, as below > BusLogic Parallel > LSI Logic Parallel, > LSI Logic SAS > VMware Paravirtual SCSI > > Currently CloudStack supports following combinations only. > DATA volumes - SCSI controller (LSI Logic Parallel) - Hard coded in > source code, no option for user to edit/choose the controller type > ROOT volumes - IDE or SCSI (LSI Logic Parallel) - Baed on value of global > configuration parameter "vmware.root.disk.controller" > > Currently the instances are deployed with the the LSI Parallel controller > type. This might result in failure to boot when attempting to deploy > templates that use the LSI SAS controller. > > CloudStack should provide administrator the means to choose the type of disk > controller (including sub types listed in introduction section > above) for an instance. The controller to be used by VM to access virtual > disk (volume) can decided for various reasons. Some of them are > listed here, > * Some controllers are optimized for best performance over specific backend > infrastructure like SAN. Ex: VMware Paravirtual SCSI > * Compatibility of some controllers with VM's virtual hardware version or > guest operating system. > * Operating system vendor recommendation and default set of drivers > distributed as part of operating system image. Ex: Windows 8.1 ISO > doesn't have Lsi Logic Parallel SCSI drivers by default. Hence a virtual disk > attached to this controller won't accessible during installation of > OS using the ISO. > > CloudStack should provide administrator an option which auto detects the > recommended disk controller for the instance's guest operating > system and applicable virtual hardware version. > Kindly let me know your thoughts. > > JIRA ticket - CLOUDSTACK-4787 > > Note:- Detailed Functional Specification is to be added at cwiki.apache.org > under 4.4 Design documents. Currently cwiki.apache.org is > down. Waiting for the site to come up to add the FS document. Added the details FS at https://cwiki.apache.org/confluence/display/CLOUDSTACK/Granular+SCSI+Controller+support+in+CloudStack+over+VMware+deployments > > Regards, > Sateesh
