Troubleshooting Vmps; Troubleshooting Dynamic Ports; Vmps Example - Cisco WS-C2948G-GE-TX Configuration Manual

Chapter 12 Configuring Dynamic VLAN Membership with VMPS

Troubleshooting VMPS

Table 12-2
enable or the download vmps command.
Table 12-2 VMPS Error Messages
VMPS Error Message
TFTP server IP address is not configured.
Unable to contact the TFTP server 172.16.254.222.
File "vmps_configuration.db" not found on the TFTP
server 172.16.254.222.
Failed to download VMPS configuration file. Out of
memory.
Download aborted. File size larger that download
buffer
After VMPS successfully downloads the VMPS database configuration file, it parses the existing file on
the VMPS server and builds a database. When the parsing is complete, VMPS displays statistics about
the total number of lines parsed and the number of parsing errors.
To obtain more information on VMPS parsing errors, set the syslog level for VMPS to 3 using the set
logging level vmps command.

Troubleshooting Dynamic Ports

A dynamic port might shut down under these circumstances:
•
•
To reenable a dynamic port that has been shut down, enter the set port enable command.
When you move a PC from a hub that is connected to the switch to a direct port on the VMPS client,
both ports remain assigned to the same VLAN.
The VMPS query and response messages are multicast packets with a destination address
of 01000CCCCCCD.

VMPS Example

Figure 12-1
switches with dynamic ports. In this example, the following assumptions apply:
•
•
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide—Release 8.2GLX
78-15908-01
shows the VMPS error messages that you might see when you enter the set vmps state
VMPS is in secure mode, and it is illegal for the host to connect to the port. The port shuts down to
prevent the host from connecting to the network.
More than 50 active hosts reside on a dynamic port.
shows a network with a VMPS server switch, two backup VMPS servers, and VMPS client
The VMPS server and the VMPS client are separate switches.
Switch 1 is the primary VMPS server.
Recommended Action
Specify the TFTP server address using the set vmps tftpserver
ip_addr [filename] command.
Enter a static route (using the set ip route command) to the
TFTP server.
Check the filename of the VMPS database configuration file on
the TFTP server. Verify that the permissions are set correctly.
The VMPS database file might have more than 256 different
VLANs specified. Reduce the number of VLANs that are used
in the file.
The VMPS database file is longer than 21051 lines. If possible,
shorten the file.
VMPS Example
12-11