[计算机硬件及网络]CloudStack存储技术.pdfVIP

CloudStack 技术分享—Storage 沈楠 天云趋势科技有限公司 测试工程师 CCIA, VCP, NASAP Steven_Shen@ 虚拟机在线迁移-XenMotion Live Migration 共享存储 More about XenMotion XenMotion in Detail XenMotion – Live VM Movement • XenMotion allows minimal downtime movement of VMs between physical systems • Generally 150-200ms of actual “downtime” • Most of the downtime is related to network switch moving IP traffic to new port XenMotion CPU Requirements • XenMotion requires systems that have similar CPUs • Must be the same manufacturer • Must be the same type • Can be different speed • Example Xeon 51xx series chips • Could have a mix of 5130 and 5120 chips Pre-Copy Migration: Round 1 • Systems verify correct storage and network setup on destination server • VM Resources Reserved on Destination Server Source Virtual Machine Destination Pre-Copy Migration: Round 1 • While source VM is still running XenServer copies over memory image to destination server • XenServer keeps track of any memory changes during this process Pre-Copy Migration: Round 1 Pre-Copy Migration: Round 1 Pre-Copy Migration: Round 1 • After first pass most of the memory image is now copied to the destination server • Any memory changes during initial memory copy are tracked Pre-Copy Migration: Round 2 • XenServer now does another pass at copying over changed memory Pre-Copy Migration: Round 2 Pre-Copy Migration: Round 2 • Xen still tracks any changes during the second memory copy • Second copy moves much less data • Also less time for memory changes to occur Pre-Copy Migration: Round 2 Pre-Copy Migration • Xen will keep doing successive memory copies until minimal differences