<MSｺﾞｼｯｸ(等幅ﾌｫﾝﾄ)でみてね>
PC
|
interface Ethernet0/0------------+ x +--------PC(新たにIP付与)
ip address 192.168.0.1/24 |
interface Ethernet0/1---------------[HUB]--------->192.168.1.254
ip address 192.168.0.1/24
interface Ethernet0/2-----------PC
ip address 192.168.2.1/24
interface Ethernet0/3-----------PC
ip address 192.168.3.1/24
interface Ethernet0/4--------------------------->192.168.4.254
ip address 192.168.4.1/24

よくないので、こうしなさい。。。