Format the USB flash disk first: Use fdisk-L to view the USB flash disk to the mount point, for example,/dev/sdb1. Unmount the USB flash disk and run the format command mkfs. vfat/dev/sdb1.
Then re-mount the USB flash drive to create the boot disk:
# dd if=/ntfs/linux_all/sys/CentOS-7.0-1406-x86_64-DVD.iso of=/dev/sdb
Note that/dev/SDB is not/dev/sdb1 and an error is returned.
In this case, you can re-open a terminal and run the DD command to the user: # While killall-usr1 dd; do sleep 5; done
Then, run the DD command to the terminal to display the burning progress:
3618528+0 records in3618528+0 records out1852686336 bytes (1.9 GB) copied, 392.471 s, 4.7 MB/s3673141+0 records in3673141+0 records out1880648192 bytes (1.9 GB) copied, 397.562 s, 4.7 MB/s3726407+0 records in3726407+0 records out1907920384 bytes (1.9 GB) copied, 402.54 s, 4.7 MB/s3779793+0 records in
Dd command:
Dd is a very useful command in Linux/Unix. It is used to copy an object with a specified size block and perform the specified conversion at the same time.
Parameters
1. If = File Name: Enter the file name. The default value is standard input. Specifies the source file. <If = inputfile>
3. IBS = Bytes: Read bytes at a time, that is, specify the size of a block to bytes.
Obs = Bytes: outputs bytes at a time, that is, specify a block size as bytes.
BS = Bytes: set the size of the read/output block to bytes at the same time.
4. CBS = Bytes: bytes are converted at a time, that is, the size of the conversion buffer zone is specified.
5. Skip = blocks: the blocks are skipped from the beginning of the input file and then copied.
6. Seek = blocks: the blocks are skipped from the beginning of the output file and then copied.
Note: It is valid only when the output file is a disk or tape, that is, it is backed up to a disk or tape.
7. Count = blocks: copy only blocks. The block size is equal to the number of bytes specified by IBS.
8. Conv = Conversion: Convert the file with the specified parameter.
ASCII: Convert ebcdic to ASCII
Ebcdic: Convert ASCII to ebcdic
IBM: Convert ASCII to alternateebcdic
Block: converts each row to the length of CBS. spaces are used to fill the remaining parts.
Unblock: the length of each row is CBS, and the remaining part is filled with spaces.
Lcase: converts uppercase to lowercase.
Ucase: converts lowercase to uppercase.
Swab: swap each pair of input bytes
Noerror: Do not stop when an error occurs
Notrunc: the output file is not truncated.
Sync: Fill each input block into IBS bytes, and fill the remaining part with null (NUL) characters.
Centos uses the DD command to create a USB disk boot disk
