Which modem model do you have? ... View more

I have looked at your config again. The DHCP pool CORPORATE_WIFI_5GHZ is nowhere configured on the router, is this correct ?   Either way, I made a few changes to your config (marked in bold):   version 15.6 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname m2-rtr-02 ! boot-start-marker boot-end-marker ! no aaa new-model ! ip routing ! ip dhcp excluded-address 10.0.0.1 10.0.0.65 ip dhcp excluded-address 192.168.100.1 192.168.100.63 ip dhcp excluded-address 10.0.11.1 10.0.11.63 ip dhcp excluded-address 10.0.10.1 10.0.10.63 ip dhcp excluded-address 10.0.12.1 10.0.12.63 ! ip dhcp pool CORPORATE_WIFI_5GHZ network 10.0.12.0 255.255.255.0 default-router 10.0.12.20 dns-server 8.8.8.8 8.8.4.4 lease 7 ! ip dhcp pool office network 10.0.0.0 255.255.255.0 default-router 10.0.0.20 dns-server 8.8.8.8 8.8.4.4 lease 7 ! no ip domain lookup ip domain name office.domain.com ip name-server 10.0.0.20 ip name-server 8.8.8.8 ip name-server 8.8.4.4 no ip cef no ipv6 cef ! multilink bundle-name authenticated ! interface Embedded-Service-Engine0/0 no ip address no ip route-cache shutdown ! interface GigabitEthernet0/0 description Outside World no ip address no ip route-cache duplex auto speed auto pppoe enable group global pppoe-client dial-pool-number 10 ! interface GigabitEthernet0/1 ip address 10.0.0.20 255.255.255.0 ip nat inside ip virtual-reassembly in no ip route-cache duplex auto speed auto no mop enabled ! interface GigabitEthernet0/1.10 description --> Data vlan encapsulation dot1Q 10 ip address 10.0.10.0 255.255.0.0 ip nat inside ip virtual-reassembly in no ip route-cache ! interface Dialer1 mtu 1492 ip address negotiated ip nat outside ip virtual-reassembly in encapsulation ppp dialer pool 10 dialer-group 10 ppp authentication pap callin ppp pap sent-username USERNAME password 0 PASSWORD --> no ppp ipcp route default ! ip forward-protocol nd ! ip http server ip http port 8080 ip http access-class 20 ip http authentication local ip http secure-server ip http timeout-policy idle 60 life 86400 requests 10000 ! ip dns server ip nat inside source route-map ISP interface Dialer1 overload ip route 0.0.0.0 0.0.0.0 Dialer1 ip ssh version 2 ! dialer-list 10 protocol ip permit ! snmp-server community public RO access-list 1 permit 10.0.0.0 0.0.0.255 ! route-map ISP permit 10 match ip address 1 match interface Dialer 1 ! control-plane ! vstack ! line con 0 login local line aux 0 line 2 no activation-character no exec transport preferred none transport output pad telnet rlogin lapb-ta mop udptn v120 ssh stopbits 1 line vty 0 4 access-class 20 in login local transport input ssh ! scheduler allocate 20000 1000 ! end ... View more

Hello,   Set the ip mtu on the dialer interface to 1492:   Interface Dialer1 Ip mtu 1492 ... View more