NetApp FAS系列存储架构-文档资料

1、Tag line, tag lineWrite and Read Request ProcessingData ONTAP Fundamentals2Objectives At the end of this module, you will be able to: Describe the writing and reading of data to and from a WAFL file system on a volume Describe the WAFL file system, including consistency points, RAID management, and

2、storage levels Describe how RAID is used to protect disk data Describe how the WAFL file system processes write and read requests3Data ONTAP SimplifiedData ONTAP Writes ReadsStorageRAIDWAFLProtocolsNetworkClientClientClientClientClientPhysical MemoryDisksNetworkData ONTAPNVRAM4Write Requests Write r

3、equests come into Data ONTAP through a variety of different interface protocols CIFS NFS FCP iSCSI HTTP WebDAV Write requests are buffered into System memory NVRAMData ONTAPWrites Reads5Data Flow: Write Request Write Buffer Windows ClientRS-232NVRAMNVLOGHBASAN HostWAFLRAIDNICStorageNFS ServiceSAN Se

4、rviceCIFS ServiceProtocolsNetworkNetworkStackMemoryBufferACKNVRAM FullNVLOGNVLOGNVLOGNVLOGACKACKACKACKUNIX Client6 UNIX ClientWindows ClientRS-232HBASAN HostWAFLRAIDData Flow: Write Request WAFL to RAIDNICStorageNFS ServiceSAN ServiceCIFS ServiceProtocolsNetworkNetworkStackMemoryBufferNVRAMNVLOGNVLO

5、GNVLOGNVLOGNVLOG7 UNIX ClientWindows ClientRS-232HBASAN HostWAFLRAIDData Flow: Write Request RAID to Storage4KStorageNFS ServiceSAN ServiceCIFS ServiceProtocolsNetworkNetworkStackMemoryBufferNVRAMNVLOGNVLOGNVLOGNVLOGNVLOG8 UNIX ClientWindows ClientRS-232HBASAN HostWAFLRAIDData Flow: Write Request St

6、orage WritesNICStorageNFS ServiceSAN ServiceCIFS ServiceProtocolsNetworkNetworkStackMemoryBufferNVRAMNVLOGNVLOGNVLOGNVLOGNVLOG9NVRAM Data ONTAP writes from system memory Note: NVRAM is never used for normal write operations NVRAM is backed up with a battery If system failure occurs before the comple

7、tion of the consistency point: then data is written from NVRAM when the system is brought back online or by the partner machine in an active-active environment 10Read Requests Every time a read request is received, WAFL determines whether to either: Read the data from the system memory (aka cache) R

8、ead the data from the disks The cache is populated by: Data that recently was written to disk Data that recently was read from diskData ONTAPWritesReads11Data Flow: Read Request Cache Windows ClientRS-232HBASAN HostWAFLRAIDNICStorageNFS ServiceSAN ServiceCIFS ServiceProtocolsNetworkNetworkStackMemoryBufferUNIX ClientCacheNVRAMNVLOGNVLOGNVLOGNVLOGNVLOG12Data Flow: Read Request Read from Disk Windows ClientRS-232HBASAN HostWAFLRAIDNICStorageNFS ServiceSAN ServiceCIFS ServiceProtocolsNetworkNetworkStackMemoryBufferUNIX ClientNVRAMNVLOGNVLOGNVLOGNVLOGNVLOGCa