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Why is my laptop no pulling an IP address when connected through the phone to a 200 series switch?

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TitleWhy is my laptop no pulling an IP address when connected through the phone to a 200 series switch?
Question
Why is my laptop no pulling an IP address when connected through the phone to a 200 series switch?
 
Environment
  • Series 200 switches
  • VOIP phones
  • Voice and Data vlans
  • CLI
  • Telnet
Answer
Voice and Data are on separate VLANs and the switchport is configured as a trunk port; however the Data vlans has not been included in the allowed VLANs list.

The phone which is connected to the switch appears in the mac address table but the computer connected to the phone does not:

 
#show mac-addr-table interface 1/0/8

MAC Address         VLAN ID      Status
-----------------  ---------  ------------
01:10:52:19:DA:D8     10        Learned

Telnet into switch and add the Data VLAN to the interface allowed vlans by running these commands:

Example:
  • Voice VLAN: 10
  • Data VLAN: 20
  • VOIP phone on VLAN 10
  • Laptop on VLAN 20
  • Interface: 1/0/8
 
>en
#configure
(Config)#interface 1/0/8
(Interface 1/0/8)#switchport trunk allowed vlan 10,20
(Interface 1/0/8)#write mem
(Interface 1/0/8)#end
#show mac-addr-table interface 1/0/8

#   MAC Address      VLAN ID     Status
-----------------  ---------  ------------
01:10:52:19:DA:D8     10        Learned
C3:D0:50:F1:CF:B9     20        Learned
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