Today, i had problem wtih my trunking cisco catalyst c2950. one of my access port to fibre optic interconnection was problem. after one hour i try to find solution for this matter.
this is log problem show:
%SPANTREE-7-RECV_1Q_NON_TRUNK: Received 802.1Q BPDU on non trunk FastEthernet0/1 VLAN2.
004964: May 4 00:01:17.302: %SPANTREE-7-BLOCK_PORT_TYPE: Blocking FastEthernet0/1 on VLAN0002. Inconsistent port type.
status of the port show that operational mode change into trunk (before access).
#sh int fa0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative Mode: dynamic desirable
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 2 (VLAN0002)
Trunking Native Mode VLAN: 1 (default)
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
After i change to static access it’s running again
#sh int fa0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative Mode: static access
Operational Mode: static access
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: native
Negotiation of Trunking: Off
Access Mode VLAN: 2 (VLAN0002)
Trunking Native Mode VLAN: 1 (default)
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
In the majority of cases, the reason for detection of STP inconsistency on the port is apparent:
Access port receives an IEEE 802.1Q-tagged SSTP BPDU.
In this scenario, access port on bridge A receives, from bridge B, a tagged PVST+ BPDU from STP of a VLAN other than 1. The port on A will be put into type-inconsistent state.
Note: The switches need not be connected directly; if they are connected through one or more IEEE 802.1D or IEEE 802.1Q switches—or even hubs—then the effect is the same.
IEEE 802.1Q trunking port receives an untagged SSTP BPDU with a VLAN type, length, value (TLV) that does not match the VLAN where the BPDU was received.
-
In this scenario, the trunk port on A receives a PVST+ BPDU from STP of VLAN 2 with a tag of VLAN 2. This triggers the port on A to be blocked in both VLAN 1 and VLAN 2.
-
The port is configured for IEEE 802.1Q trunking on one side but the other side is access port.
-
IEEE 802.1Q trunks are on both sides, but the Native VLANs are different.
In these cases, fix the configuration mismatch to resolve the STP inconsistency.
If devices on both ends of a point-to-point link are Cisco Catalyst switches, an examination of the local and remote port configuration typically reveals the configuration mismatch:
Post a Comment