A."--permanent"B."--zone"C."--add-service"D."--reload"
A.yum -y install dhcpB.yum -y install dhcpdC.yum -y install dhcpcliD.yum -y install dns
A.空殼郵件服務器既可以接收郵件,也可以轉(zhuǎn)發(fā)郵件B.空殼郵件服務器只接收郵件C.空殼郵件服務器只轉(zhuǎn)發(fā)郵件D.空殼郵件服務器既不接收也不轉(zhuǎn)發(fā)郵件