进行修改：

shared-network 250-251{  subnet 192.168.250.0 netmask 255.255.255.0{    option routers 192.168.250.1;    range 192.168.250.2192.168.250.254;}  subnet 192.168.251.0 netmask 255.255.255.0{    option routers 192.168.251.1;    range 192.168.251.2192.168.251.200;}