Cisco Phones Receiving DHCP IP from wrong VLAN on EXOS switches with Cisco Router DHCP

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I have an X430-24p running 15.5.3.4. The switch runs to a Cisco router that has DHCP running on it. Voice and Data VLANS were configured on the switch and router.

Ports are configured with the Data VLAN untagged and the Voice VLAN tagged. The trunk port to the router has both VLANs tagged.

Our Cisco phones are pulling their IPs from the wrong VLAN. It looks like all traffic leaving the switch is tagged with the Data VLAN.

When I run sh iparp, it shows all hosts are in the Data VLAN. Can anyone give me a clue how to allow the phones to receive their correct VLAN IP from DHCP on a Cisco Router, via an EXOS switch?
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Ignatius

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Posted 2 years ago

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Patrick Voss, Alum

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Hello Ignatius,

This is normal behavior unless the phones are specifically told to send traffic into the voice VLAN. I would recommend taking a look at this article to configure LLDP:

https://gtacknowledge.extremenetworks.com/articles/How_To/How-to-configure-LLDP-for-Extreme-switches...

This should do the trick.
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Ignatius

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That did the trick! Brilliant! Many thanks!