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IP phone does not work while Connecting IP Phones to Switches through NAC Authentication and Voice VLAN.

Latest reply: Jul 6, 2018 07:39:58 723 1 0 0 0
Issue Description

IP phone does not work while Connecting IP Phones to Switches through NAC Authentication and Voice VLAN.

After plug out and plug in cable from the phone then IP phone goes in the same stage its showing retrying and not be able to sign in.

Then after implementing this step [switch-aaa]cut access-user user-id 968

Then IP phone comes up.

version: V200R008C00SPC500

Customer follow the product document as below:


transparent.gif Handling Process

Below is the test step:

<switch>dis access-user interface g 0/0/8

Info: No online user.

plug in the IP Phone.


Enter system view, return user view with Ctrl+Z.

[switch]dis access-user interface g 0/0/8


 UserID Username                IP address       MAC            Status


 956    MISHARI\mkamran    6400-6a34-0402 Success

 968                            FE80::625:C5FF:FEDE:8F9B

                                                 0425-c5de-8f9b Success


 Total: 2, printed: 2

Now, it is online with IPV6 address and not working, so we do below step:


[switch-aaa]cut access-user user-id 968

Info: Total 1  user(s) being cut.


Then display access-user to check the IP phone, it is online with IPV4 address and working fine.

transparent.gif Root Cause

If the terminal sends ipv6 ARP, the switch refreshes the ipv6 table. So we need make it online with IPV4 address.

transparent.gif Solution
Disable IPV6 and it is working fine.

acl number 4001 

rule 5 deny l2-protocol ipv6

traffic classifier ipv6 operator and

if-match acl 4001

traffic behavior ipv6


traffic policy ipv6

classifier ipv6 behavior ipv6

traffic-policy ipv6 global inbound

  • x
  • convention:

Created Jul 6, 2018 07:39:58

good case
View more
  • x
  • convention:


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