Data ONTAP for netapp Storage

Data. Tap is a UNIX-type operating system modified based on UNIX. The original source code is from the Berkeley source code and needs to be optimized for filer file system access.
OK Code Optimized. It combines the wfal file system and the microkernel to design a number of patents and has high performance in file processing. It can be said that it is an OS dedicated for data processing, and its kernel is extremely small,
The size is smaller than 2% of the general OS. (Here we can think of IBM
Ds8000, which uses the P host AIX as the operating system. Of course, it is unclear if it has been modified ). Data
Third-party software and scripts cannot be installed on. Tap. Storage software (including standard and optional software) has been directly embedded into the kernel. The main architecture of data. Tap consists of three parts:
The first part is the interface, which includes the network interface (GBE-fiber/Copper, TCP/IP Offload Engine) and the optical fiber interface (2gb-fiber channel ). Of course, in the OS layer, the interface refers to the interface driver. Program .
The second part is the communication protocol, including file protocol (NFS, CIFS, HTTP, dafs) and block protocol (FCP, iSCSI ). Netapp can provide these protocols externally. FCP and SCSI
Third, the file system wafl and the integrated raid Disk Array System (Integrated raid manager ).

The figure above shows the basic structure of data. Tap. It contains a series of closely connected processing modules to respond to NFS, CIFS, and HTTP requests. The access request starts with the NIC and initiates the hard disk I/O request through the network protocol layer and file system. When the file system responds to the request, it sends a response to the network layer.

The kernel is stored in the CF card. When the system is started, the OS kernel is retrieved from CF by default.
If there is no kernel in CF, It is retrieved from the physical hard disk. If it still does not exist, it is started from a floppy disk (a system without CF. It is estimated that such products are no longer available ). Each storage system will belong to a system
System hard disk. These hard disks are also in the inventory. When the system starts, the configuration file information is read from/etc. In fact, there is also a/etc copy in CF.