With the VLAN Trunk Protocol/VLAN Query Protocol (VTP/VQP) Statistics page, you can:
A switch transmits advertisements on all of its trunk ports immediately after a VLAN configuration change. It also transmits periodic summary advertisements on any trunk port for which it has not sent or received an advertisement for the last 5 minutes. By hearing these advertisements, all switches in the same management domain learn about new VLANs configured in the transmitting switch. After a switch learns about a VLAN, it receives all frames on that VLAN from any trunk port and forwards them to each of its trunk ports.
Advertisements are transmitted on the default VLAN that corresponds to the type of trunk link. For Ethernet, the default VLAN is 1.
Receive Statistics:
| Summary Adverts | Number of summary advertisements received by this switch on its trunk ports. Summary advertisements contain the management domain name, the configuration revision number, the update timestamp and identity, the authentication checksum, and the number of subset advertisements to follow. |
| Subset Adverts | Number of subset advertisements received by this switch on its trunk ports. Subset advertisements contain all the information for one or more VLANs. |
| Advert Requests | Number of advertisement requests received by this switch on its trunk ports. Advertisement requests normally request information on all VLANs. They can also request information on a subset of VLANs. |
Transmit Statistics:
| Summary Adverts | Number of summary advertisements sent by this switch on its trunk ports. Summary advertisements contain the management domain name, the configuration revision number, the update timestamp and identity, the authentication checksum, and the number of subset advertisements to follow. |
| Subset Adverts | Number of subset advertisements sent by this switch on its trunk ports. Subset advertisements contain all the information for one or more VLANs. |
| Advert Requests | Number of advertisement requests sent by this switch on its trunk ports. Advertisement requests normally request information on all VLANs. They can also request information on a subset of VLANs. |
Configuration Errors:
| Revision Errors | Number of revision errors. Whenever you define a new VLAN or delete, suspend, resume, or modify the parameters of an existing VLAN, the configuration revision number of the switch increments. The number of revision errors increments whenever the switch receives an advertisement whose revision number matches the revision number of the switch but whose MD5 digest values do not match. This error indicates that the VTP password in the two switches is different or that the switches have different configurations. These errors indicate that the switch is filtering incoming advertisements, which causes the VTP database to become unsynchronized across the network. |
| Digest Errors | Number of MD5 digest value errors. The number of digest errors increments whenever the MD5 digest in the summary packet and the MD5 digest of the received advertisement calculated by the switch do not match. This error usually indicates that the VTP password in the two switches is different. To solve this problem, make sure the VTP password on all switches is the same. These errors indicate that the switch is filtering incoming advertisements, which causes the VTP database to become unsynchronized across the network. |
| V1 Summary Errors | Number of version 1 errors. The number of version 1 summary errors increments whenever a switch in VTP V2 mode receives a VTP version 1 frame. This error indicates that at least one neighboring switch is either running VTP version 1 or VTP version 2 with V2 mode disabled. To solve this problem, change the configuration of the switches in VTP V2 mode to disabled. |
The following table describes each VQP statistic.
| Queries | Number of queries sent by the client to the VLAN Membership Policy Server (VMPS). |
| Wrong Version Responses | Number of times the version field in the query packet contained a value that is greater than the version supported by the VMPS. Previous VLAN assignment of the port is not changed. The switch only sends VMPS version 1 requests. |
| Wrong Domain Responses | Number of times the management domain in the request did not match the one for the VMPS. Any previous VLAN assignments of the port are not changed. Receipt of this response indicates that the server and the client have not been configured with the same VTP management domain. |
| No Resource Responses | Number of times the VMPS is unable to answer the request because of a resource availability problem. If the retry limit has not yet been reached, the client sends the request to the same server or to the next alternate server, depending on whether the per-server retry count has been reached. |
| Responses | Number of responses sent by the VMPS to the client. |
| Denied Responses | Number of times the VMPS denied the client request for security reasons. When the VMPS response says to deny an address, no frame is forwarded to or from the workstation with that address (broadcast or multicast frames are delivered to the workstation if the port has been assigned to a VLAN). The client keeps the denied address in the address table as a blocked address to prevent further queries from being sent to the VMPS for each new packet received from this workstation. The client ages the address if no new packets are received from this workstation on this port within the aging time period. |
| Shutdown Responses | Number of times the VMPS sent a response to shutdown the port. The client disables the port and removes all dynamic addresses on this port from the address table. You must administratively reenable the port to restore connectivity. |
| VMPS Changes | Number of times that the VMPS changed from one server to another. |
You can reset VTP and VQP statistics by clicking Reset. After the values are reset, they automatically begin to increment.