What should I do when my Internet access dial-up connection fails？

03-24-2022
43020
VX420-G2h V1

Note: This Article Applies to Dialing failure caused by physical layer connection and Dialing failure caused by internet access problems

Module I. Physical layer connection

Part 1. Physical layer interface check

  1. Check the Internet corresponding interface indicator light connection

PON(GPON/EPON) LED:

Light Flash to On

The router is registered with the OLT

DSL(ADSL/VDSL) LED:

Light Flash to On

DSL synchronization is complete.

WAN LED:

Light On

Powered device is connected to the associated port but no traffic

Part 2. Web page information check

  1. Check the connection state for the web page

Part 3. The debug information of the serial port

Module II. Dial-up connection

Part 1. IPv4

  1. PPPoE

• Check the settings of PPPoE dial-up

• Username/password

• Host unique

• MTU value: The size of the package when it is forwarded, and when that value is exceeded, it needs to be sliced

• The interaction process of PPPoE dial-up

  1. PPTP

• The second connection (usually dynamic or static) can dial the number, and the first connection cannot dial the number

• PPTP Server Address is not correct

• Problems with double - connection applications

The First Connection information and corresponding interactive packages:

The Second Connection information and corresponding interactive packages:

  1. L2TP

• The second connection (usually dynamic or static) can dial the number, and the first connection cannot dial the number

• L2TP Server Address is not correct

• Problems with double - connection applications

The First Connection information and corresponding interactive packages:

The Second Connection information and corresponding interactive packages:

  1. DHCP

• DHCP server dial-up interactive process

• Check the IP Address, DNS, Gateway when dial-up successfully

• Grab the packages of dial-up process

Part 2. IPv6

  1. PPPoE and SLAAC

• Verify that the PPPoE username password is incorrect

• IPv4 has address while IPv6 has no address

Step1: Grab packages to check the PPPoE dial-up status

Step2: Grab packages to check the SLAAC dial-up status

*RS represents the Router Solicitation message. RA messages represent the Router Advertisement.

*When grabbing the PPPoE packages, the filter condition is set to ppp || pppoed

*When grabbing the SLAAC packages, the filter condition is set to dhcpv6 || icmpv6

  1. DHCP and SLAAC

• To check whether IPv4 has address but IPv6 has no address

• To check whether wan has IPv6 address but the LAN has no IPv6 address

Step1: Grab packages to check the DHCP dial-up status

Step2: Grab packages to check the SLAAC dial-up status

*When grabbing the DHCP packages, the filter condition is set to bootp

* When grabbing the SLAAC packages, the filter condition is set to dhcpv6 || icmpv6

  1. PPPoE and DHCPv6

• Verify that the PPPoE username password is incorrect

• To check whether IPv6 has no address or not

Step1: Check the DHCPv6 messages

Step2: INA is the wan address of the router and PD is the prefix of the lan port device

Step3: Grab packages to check the PPPoE dial-up status

Step4: Grab packages to check the DHCPv6 dial-up status

*When grabbing the PPPoE packages, the filter condition is set to ppp || pppoed

*When grabbing the DHCPv6 packages, the filter condition is set to dhcpv6

  1. DHCP and DHCPv6

• To check whether IPv4 has address but IPv6 has no address

• To check whether IPv6 has no address or not

Step1: Grab packages between lan and wan port to check the packages of DHCP and ICMPv6 (RS RA)

Step2: Grab packages to check the DHCP dial-up status

Step3: Grab packages to check the DHCPv6 dial-up status

  1. PD Only

Step1: Special dialing requirements for Russia and Brazil

Step2: To check whether the software version supports the dial mode or not

Step3: To check the PD fields of the DHCPv6 message between the DUT and server

Step4: PD detail information

Note : The PD fields represent the Prefix Delegation

Part 2. IPv6 Only

  1. SLAAC

• Check to see if the ICMPv6 RS/RA message between DUT and Server is working

  1. DHCPv6

• Check whether the IANA, DNS and PD fields in the message are normal

• Check the IANA/IAPD information: