unknow protocol drops

[skelley5000]

I am seeing this on one my uplinks on a 3850 I currently have up and running.

This is a layer 2 connection that is trunked with a 3750, both ports on each switch are configured for the correct VLAN's but one thing I did notice is the uplink on the 3750 has the following where the 3850 does not..

3750 uplink port

interface GigabitEthernet2/1/4
 description
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 3,6,10
 switchport mode trunk
 priority-queue out
 mls qos trust dscp

3850

interface TenGigabitEthernet1/1/3
 description
 switchport trunk allowed vlan 3,6,10
 switchport mode trunk

Would this cause the protocol drops?

[Joseph W. Doherty]

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Posting

Those statements shouldn't have anything to do with protocol drops.

More likely, one switch is transmitting a "special" protocol (e.g. VTP, DTP, etc.) that the other switch doesn't recognize.

[kevin.szatkowski]

I second Joseph's statement.  I have seen this numerously with Cisco to "non-cisco" devices with the "non-cisco" device running LLDP, though it could be another protocol.

To check for LLDP (http://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/5_x/nx-os/system_management/configuration/guide/sm_nx_os_cg/sm_lldp.html).  It needs to be turned on both for transmitting (globally or on the interface) and for receiving.

Regards,

Kevin