Frequently Asked Question

VLAN Tagging Issue with 3.0.0-040
Last Updated 2 years ago

Firmware Affected: GA 3.0.0-040, DEV 3.0.0-041
Severity: Moderate


Phone does not get a DHCP address when plugged into seemingly untagged port. Possibly related: phone does not send out voice traffic but does have other traffic.
This issue is believe to be related to the LLDP implementation. Voice VLAN tagging can be configured with LLDP-MED network policy. Some switches report VLAN ID 1 as the LLDP-MED voice VLAN and list it as untagged. This might confuse the phone which seems to wrongly interpret the data. Analysis is still being conducted.

Workarounds and Fixes:
1. Firmware fix will be reported here when available.

2. Disable LLDP on the phone - disabling LLDP has remedied this problem in the field.

3. Disable LLDP on the switch.

4. Disable LLDP-MED Network Policy on the switch

5. Explicitly configure LLDP-MED Network Policy with specific tagged VLAN - phone should be configured to this VLAN.

If you are encountering this problem or something similar please report the issue by submitting a ticket or sending an email to

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