The Design And Implementation Of Distributed Block-storage System

With the growing demand for storage as well as the rapid development of newstorage technologies,storage systems,rapid development.Toward large-capacitystorage systems,high-speed,high reliability and ease of management trends. thedevelopment of storage devices from physical constraints of the hardware itself,thestorage capacity and stability,there are certain limitations and bottlenecks. Ofparticular note is the storage system and storage hardware are usually bound tocause hardware and software can not be separated,storage hardware updates andreplaces the storage system development and application of cost and safety.This paper designs and implements a block-level distributed data storagesystem that uses inexpensive high-availability cluster will manage ordinaryPC,providing a huge virtual logical storage space within the space can be arbitrarilycreate virtual disks, each virtual disk is divided into fixed-size piece of datadistributed in different physical storage nodes. According NWR policy creates threecopies are stored in different storage devices, some of the equipment damage willnot affect the normal use.This supports storage devices heterogeneous environments,storage capacitygreater load capacity equipment,the system can automatically depending on the loadcapacity of the device,according to a certain ratio between the use of storageresources for each storage device,.To ensure data security,designed for virtual disk snapshot function,usetechnology to achieve Cowper-write snapshot technology that can quickly carry outthe virtual disk data differential backup,in case of continuous system operationquickly create data backup, create snapshot virtual disk can be restored at any time.Traditional storage technology development today, a storage area network(SAN) technology is still a major industry-standard storage technology,iSCSI SANprotocol is one of the main protocol implementation,the system provides block-levelaccess interface can be used as back-end storage iSCSI Target.Proven distributed storage system to solve the storage system single point offailure,to go to the center of the multi-copy technology ensures data security,andcan provide PB levels of storage capacity. Finally, the paper conducted a functionalsystem testing and integration testing, and also for iSCSI integration also carried outfunctional and performance testing.