HP 2500 manual 11-10

Troubleshooting

Unusual Network Activity

1.If VLAN_1 (VID=1) is configured as “Untagged” on port 3 on switch “X”, then it must also be configured as “Untagged” on port 7 on switch “Y”. Make sure that the VLAN ID (VID) is the same on both switches.

2.Similarly, if VLAN_2 (VID=2) is configured as “Tagged on the link port on switch “A”, then it must also be configured as “Tagged” on the link port on switch “B”. Make sure that the VLAN ID (VID) is the same on both switches.

Duplicate MAC Addresses Across VLANs. Duplicate MAC addresses on different VLANs are not supported and can cause VLAN operating problems. There are no explicit events or statistics to indicate the presence of duplicate MAC addresses in a VLAN environment. However, one symptom that may occur is that a duplicate MAC address can appear in the Port Address Table of one port, and then later appear on another port. (This can also occur in a LAN where there are redundant paths between nodes and Spanning Tree is turned off.) For more information, refer to “VLAN Restrictions” on page 9-75.

Troubleshooting

11-10