روتر اینترنت داره ولی کلاینت نه

سلام دوستان ، روتر سیسکو 2921 رو به صورت pptp client تنظیم کردم و همه چیز اوکی هست و از داخل روتر پینگ 8.8.8.8 رو دارم. ولی از توی کامپیوترها پینگ 8.8.8.8 رو ندارم ممنون میشم اگر کسی ایراد کارم رو بگه. این کانفیگ من هست:

(router to pptp server): 
---------------------------------------
interface gig 0/0/0 
ip address 10.96.174.225 255.255.254.0 
no sh 
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(router to pc): 
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interface Gig 0/1 
ip nat inside 
ip address 172.21.2.1 255.255.255.0 
no sh 
-----------------------------------------
(Pc): 
---------------------------------------
172.21.2.2 
255.255.255.0 
172.21.2.1 
--------------------------------------
Router : 
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service internal 
vpdn enable 
vpdn-group 1 
request-dialin 
protocol pptp 
pool-member 1 
initiate-to ip 31.24.238.222 
ex 
interface Dialer0 
ip address negotiated 
encapsulation ppp 
dialer pool 1 
dialer-group 1 
dialer idle-timeout 0 
dialer string 123 
dialer vpdn 
dialer persistent 
ppp chap hostname pptphostname 
ppp chap password 0 pptppassword 
ip nat outside 
ex 

ip route 0.0.0.0 0.0.0.0 Dialer0 
ip route 31.24.238.222 255.255.255.255 10.96.174.1 

dialer-list 1 protocol ip permit 
ip nat inside source list 100 interface dialer 0 overload 
access-list 100 permit ip any any 

این هم کانفیگ کل روتر:

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Router2921#show running-config 

version 15.2 
service config 
service timestamps debug datetime msec 
service timestamps log datetime msec 
service password-encryption 
service internal 

no aaa new-model 
ip cef 

no ipv6 cef 
multilink bundle-name authenticated 
vpdn enable 
vpdn-group 1 
request-dialin 
protocol pptp 
pool-member 1 
initiate-to ip 31.24.238.222 
license udi pid CISCO2921/K9 sn FGL172711NU 
hw-module sm 1 


interface Embedded-Service-Engine0/0 
no ip address 
shutdown 
interface GigabitEthernet0/0 

interface GigabitEthernet0/1 
ip address 172.21.2.1 255.255.255.0 
ip nat inside 
ip virtual-reassembly in 
duplex auto 
speed auto 
interface GigabitEthernet0/2 
no ip address 
shutdown 
duplex auto 
speed auto 
interface GigabitEthernet000 
ip address 10.96.175.30 255.255.254.0 
ip virtual-reassembly in 
interface GigabitEthernet010 

interface GigabitEthernet1/0 
no ip address 
shutdown 
interface GigabitEthernet1/1 
description Internal switch interface connected to Service Module 
no ip address 
interface Vlan1 
no ip address 
interface Dialer1 
ip address negotiated 
ip access-group 101 in 
ip access-group 101 out 
ip nat outside 
ip virtual-reassembly in 
encapsulation ppp 
dialer pool 1 
dialer remote-name david 
dialer idle-timeout 0 
dialer string 1234 
dialer persistent 
dialer vpdn 
dialer-group 1 
ppp pfc local request 
ppp pfc remote apply 
ppp eap refuse 
ppp chap hostname pptpusername 
ppp chap password 7 0000335F550953535A711C1A59 
ppp ms-chap refuse 
ppp pap refuse 
no cdp enable 
ip forward-protocol nd 
no ip http server 
no ip http secure-server 
ip nat inside source list 100 interface Dialer1 overload 
ip route 0.0.0.0 0.0.0.0 Dialer1 
ip route 31.24.238.0 255.255.255.0 10.96.174.1 
access-list 100 permit ip any any 
access-list 101 permit ip any any 
dialer-list 1 protocol ip permit 

اینم خروجی نت :

Router2921#show ip nat translations
Pro Inside global      Inside local       Outside local      Outside global
icmp 172.16.3.234:1    172.21.2.2:1       4.2.2.4:1          4.2.2.4:1
udp 172.16.3.234:51517 172.21.2.2:51517   4.2.2.4:53         4.2.2.4:53
udp 172.16.3.234:52168 172.21.2.2:52168   4.2.2.4:53         4.2.2.4:53
udp 172.16.3.234:52579 172.21.2.2:52579   4.2.2.4:53         4.2.2.4:53
tcp 172.16.3.234:58283 172.21.2.2:58283   2.22.144.112:80    2.22.144.112:80