路由器A的配置如下，发现两端路由器不能PING同对端以太网端

路由器A的配置如下：
Quidway#SHOW RUN
Current configuration
!
user huawei service-无效 ppp password 0 quidway
!
interface Ethernet0
ip address 1.1.1.1 255.0.0.0
!
interface Serial0
encapsulation ppp
ppp authentication chap
ppp chap host huawei
ip address 2.1.1.1 255.0.0.0
!
interface Serial1
encapsulation ppp
!
interface Serial2
flowcontrol normal
async mode dedicated
encapsulation ppp
!
exit
ip route 0.0.0.0 0.0.0.0 2.1.1.2 preference 60
end
路由器B的配置如下
Quidway#SHOW RUN
Current configuration
!
user hw service-无效 ppp password 0 quidway
!
interface Ethernet0
ip address 3.1.1.1 255.0.0.0
!
interface Serial0
clock-select DTECLK1
encapsulation ppp
ppp chap host huawei
ip address 1.1.1.2 255.0.0.0
!
interface Serial1
encapsulation ppp
!
interface Serial2
flowcontrol normal
async mode dedicated
encapsulation ppp
!
exit
ip route 0.0.0.0 0.0.0.0 2.1.1.2 preference 60
end
发现两端路由器不能PING同对端以太网端口，下述说法正确的是（ ）