Recalling the partitions and file systems
Partition type
primary partition: a total of a maximum of four
extended partition, only one, it is also regarded as a kind of primary partition, that primary partitions plus an extended partition up to four. But the extended partition and format the data can not be stored, must be subdivided into logical partitions to use
logical partitions: a partition in the extended partition, if it is IDE hard disk, Linux supports up to 59 logical partitions, if SCSI hard disk Linux supports up to 11 logical partitions
File system
ext2: ext file system is an upgraded version of the system Red Hat Linux 7.2 version of the previous default is ext2 file system. Released in 1993, partitioning and maximum 2TB file maximum support to 16TB (1TB = 1024GB = 1024 * 1024KB)
ext3: ext3 file system is an upgraded version of the ext2 file system, the biggest difference is that with a log function to improve when the system suddenly stopped reliability of the file system. Support partitioning and maximum 2TB to 16TB maximum file
ext4: it is the ext3 file system upgrade. ex4 been a number of improvements in performance and reliability of the trial reduction. EXT4 change can be said to be earth-shaking, such as backward compatible with EXT3, the largest 1EB file system and a 16TB file, unlimited number of subdirectories, Extents continuous data block concept, multi-block allocation, delayed allocation, pre-allocated persistent, fast FSCK, log school inspection, no log mode, online defragmentation, inode enhancement is enabled by default barrier and so on. CentoS6.3 is the default file system
(1EB = 1024PB = 1024 * 1024TB )