By default a Catalyst 9300 sends only plain LLDP until it receives LLDP-MED packets from the end device. Only then does it send LLDP with MED TLVs, such as network policy.
Checked 2026-10-02
By default, the device only sends LLDP packets until it receives LLDP-MED packets from the end device.
- Vendor
- Cisco
- Product
- Cisco Catalyst 9300 Series Switches
- Subsystem
- LLDP-MED
- Deployment
- on-premises
- Region
- not restricted
- Release range
- IOS XE 17.7.x
- Checked
- 2026-10-02
Sources
- Interface and Hardware Components Configuration Guide, Cisco IOS XE Cupertino 17.7.x (Catalyst 9300 Switches) - Configuring LLDP, LLDP-MED, and Wired Location Service — Cisco Systems · tier 2 current vendor documentation · LLDP-MED
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting IP phones that do not get a voice VLAN or DHCP options: source note ip-phone-dhcp-vlan-troubleshooting-lldp-med-after-detect. WarmTransfer. https://warmtransfer.net/knowledge/claims/ip-phone-dhcp-vlan-troubleshooting-lldp-med-after-detect
BibTeX
@misc{warmtransfer-claim-ip-phone-dhcp-vlan-troubleshooting-lldp-med-after-detect,
title = {Troubleshooting IP phones that do not get a voice VLAN or DHCP options: source note ip-phone-dhcp-vlan-troubleshooting-lldp-med-after-detect},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/ip-phone-dhcp-vlan-troubleshooting-lldp-med-after-detect},
note = {Source note ip-phone-dhcp-vlan-troubleshooting-lldp-med-after-detect, checked 2026-10-02}
}