1. 查看盘
$diskutil list
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
: GUID_partition_scheme *320.1 GB disk0
: EFI EFI 209.7 MB disk0s1
: Apple_CoreStorage 319.2 GB disk0s2
: Apple_Boot Recovery HD 650.0 MB disk0s3
/dev/disk1
#: TYPE NAME SIZE IDENTIFIER
: Apple_HFS Macintosh HD *318.9 GB disk1
Logical Volume on disk0s2
19E495B4-6D35-4E86-BB85-E12941607B8F
Unlocked Encrypted
/dev/disk2
#: TYPE NAME SIZE IDENTIFIER
: FDisk_partition_scheme *7.8 GB disk2
: 0xEF 6.4 MB disk2s2
/dev/disk2就是待写入的U盘
2. unmount U盘
$diskutil unmountDisk /dev/disk2
然后再看
$diskutil list
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
: GUID_partition_scheme *320.1 GB disk0
: EFI EFI 209.7 MB disk0s1
: Apple_CoreStorage 319.2 GB disk0s2
: Apple_Boot Recovery HD 650.0 MB disk0s3
/dev/disk1
#: TYPE NAME SIZE IDENTIFIER
: Apple_HFS Macintosh HD *318.9 GB disk1
Logical Volume on disk0s2
19E495B4-6D35-4E86-BB85-E12941607B8F
Unlocked Encrypted
/dev/disk2
#: TYPE NAME SIZE IDENTIFIER
: FDisk_partition_scheme *7.8 GB disk2
: 0xEF 6.4 MB disk2s2
3. 写入U盘
$sudo dd if=~/Downloads/CentOS-7.0--x86_64-Everything.iso of=/dev/disk2 bs=1m