Mac OS X清除DNS缓存
根据Mac OS X操作系统的版本选择以下命令：
MACOSx12(Sierra ) and later:
sudo kill all-hupmdnsrespondersudokillallmdnsresponderhelpersudodscacheutil-flushcachemacosx 11 (El capitan ) andOSx12 ) Sierrer
sudo kill all-hupmdnsrespondermacosx 10.10 (Yosemite )，版本10.10.4 :
sudodscacheutil-flushcachesudokillall-hup mdnsresponder https://help.dreamhost.com/HC/en-us/articles/214988 -