PPTP用户拨号引发的路由器权限问题

server#show run
Building configuration...

Current configuration : 1668 bytes
!
! Last configuration change at 17:09:46 UTC Wed May 16 2012
upgrade fpd auto
version 15.1
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname server
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$I9G8$C3lOYoEc6oxVnwzSEu.Iu1
!
aaa new-model
!
aaa authentication login login local
aaa authentication ppp default local
!
aaa session-id common
!
ip source-route
ip cef
!
no ip domain lookup
no ipv6 cef
!
multilink bundle-name authenticated
vpdn enable
!
vpdn-group 1
 ! Default PPTP VPDN group
 accept-dialin
  protocol pptp
  virtual-template 1
 l2tp tunnel timeout no-session 15
!
crypto pki token default removal timeout 0
!
username pptp password 0 123456
!
redundancy
!
interface Loopback0
 ip address 172.18.100.1 255.255.255.0
!
interface FastEthernet0/0
 ip address 172.18.10.1 255.255.255.0
 duplex auto
 speed auto
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Virtual-Template1
 ip unnumbered FastEthernet0/0
 peer default ip address pool pptp.pool
 ppp authentication chap pap
!
ip local pool pptp.pool 172.18.10.100 172.18.10.200
ip forward-protocol nd
 ip http server
no ip http secure-server
!
ip route 0.0.0.0 0.0.0.0 172.18.10.2
!
control-plane
!
mgcp profile default
!
gatekeeper
 shutdown
!
line con 0
 exec-timeout 0 0
 logging synchronous
 login authentication login
 stopbits 1
line aux 0
 login authentication login
 stopbits 1
line vty 0 4
 login authentication login
 transport input all
!
end