为什么做完NAT之后PPP就会down掉

ddmm1214

如题，本人是个新人，刚接触华为路由交换没多久，请各位大神多多指教，有些小白问题请多多包涵！只做的简单的PPP连接，没做NAT的时候能ping通 做完NAT就出现下面字样，然后就不通，静态，easy 都一样
R1]interface Serial4/0/0       link-protocol ppp
       ip address 10.1.1.1 255.255.255.0
       nat static global 10.1.1.11 inside 192.168.2.2 netmask 255.255.255.255
R2]interface Serial4/0/0
      link-protocol ppp
      ip address 10.1.1.2 255.255.255.0
做完NAT 出现如下：

[Huawei]
Oct 17 2017 23:46:43-08:00 Huawei %%01PPP/4/TIMEOUT(l)[5]:On the interface Seria
l4/0/0, PPP link was closed because the keepalive timer expired.
[Huawei]
Oct 17 2017 23:46:43-08:00 Huawei %%01IFNET/4/LINK_STATE(l)[6]:The line protocol
PPP on the interface Serial4/0/0 has entered the DOWN state.
[Huawei]
Oct 17 2017 23:46:43-08:00 Huawei %%01IFNET/4/LINK_STATE(l)[7]:The line protocol
PPP IPCP on the interface Serial4/0/0 has entered the DOWN state.
[Huawei]
Oct 17 2017 23:46:44-08:00 Huawei %%01RM/4/IPV4_DEFT_RT_CHG(l)[8]:IPV4 default R
oute is changed. (ChangeType=Delete, InstanceId=0, Protocol=Static, ExitIf=Seria
l4/0/0, Nexthop=10.1.1.1, Neighbour=0.0.0.0, Preference=1006632960, Label=NULL,
Metric=0)

段小艾

提示keeplive超时，你可能做反了

努力学习吴同学

没写ACL的原因？