/dev/hda /dev/hdc – IDE Hard Disk , CDROM
/dev/sda /dev/sdb – SCSI, SATA or USB Storage
/dev/md0 /dev/md1 – Software Raid Disk
ls –l using these command we can identify device type
bashscript@hosting2 ~ $ ls -l /dev/sda
brw-rw---- 1 root disk 8, 0 2010-06-04 21:55 /dev/sda
b refer to the block device
NOTE: character devices are read/write character by character – synchronous with operation
Character device are RAW device like Without parition.
Character Device -Linux /dev/tty /dev/null
/dev/tty[0—6] – Virtual Console
Virtual Console it will provide the text login . it will provide six virtual console that provide to login
/dev/null, /dev/zero – it is used for maintain the software device
/dev/random. /dev/unrandom is used to maintain the random number.
bashscript@hosting2 ~ $ ls -l /dev/random
crw-rw-rw- 1 root root 1, 8 2010-06-04 21:55 /dev/random
c reference to the charter device
NOTE: Block devices are read/write by block by block – asynchronous with operation.Block devices are with Partition.