Symptom/Cause | Solution |
|---|---|
LLDP packets not transmitted properly Interface is down LLDP agent not enabled LLDP tx not enabled | Use these commands: show lldp interface IF_NAME Verify if there are any packets discarded. show interface IF_NAME description Check if the interface is up |
LLDP packets not received properly Interface is down LLDP agent not enabled LLDP rx not enabled | Use these commands: show lldp interface IF_NAME Verify if there are any packets received in error. show interface IF_NAME description : Check if the interface is up |
LLDP system name, system description not seen in the peer Interface is down LLDP agent not enabled LLDP rx/tx not enabled Basic management capabilities are not enabled. | Use these commands: show lldp interface IF_NAME neighbor Check the neighbor information show running config Check if system name/description are configured at the sending side Note: This applies to many other lldp capabilities like ieee-8021-org-specific, ieee-8023-org-specific, and med capabilities. The needed capabilities must be enabled on the device using lldp tlv-select. |
All VLANs configured not displayed in the remote VLAN details of the peer device VLAN not configured for the interface | This is a special case where there are more than 82 vlans and the TLV size is increasing the MTU. As vlan details are encoded after encoding all the other TLVs. So whenever the buffer becomes full, the end of TLV is sent automatically and the rest of the vlan information is not displayed. This is the expected behavior. |
LLDP med capabilities are not displayed in the neighbor Interface is not up LLDP agent not enabled Tx/rx not enabled LLDP tlv-type med capabilities not enabled LLDP med dev-type has to be end point class3 at least on one side. It doesn’t sent its med capabilities if net-connect is enabled until it receives med info from the neighbor | Use these commands: show lldp interface IF_NAME Verify if tx/rx, med is enabled. show interface IF_NAME descriptio Check if the interface is up show lldp interface IF_NAME neighbor Verify the med related information of neighbor |