switch(config)#management vlan ip-address x.x.x.x mask x.x.x.x
switch(config)#no management vlan ip dhcp client
switch(config)#ip default-gateway x.x.x.x

switch(config)#sntp server 120.25.115.20 port 123	##120.25.115.20是阿里的ntp服務器

switch(config)#ip telnet server