What are some common configuration errors that can occur when configuring VLANs?

What will be an ideal response?

ANSWER: Some of the common configuration errors that can occur are as follows:
* incorrect port mode-Switch ports connected to endpoints, such as workstations and servers, should nearly always use access mode. Switch ports connected to other network devices should be configured in trunk mode only if that connection must support multiple VLANs.
* incorrect VLAN assignment-This can happen due to a variety of situations, including misconfigurations of the client authentication process in which a VLAN is assigned to the device before the authentication process is complete.
* VLAN isolation-By grouping certain nodes into a VLAN, you are not merely including those nodes-you are also excluding other groups of nodes. This means you can potentially cut off an entire group from the rest of the network. VLANs must be connected to and configured on a router or Layer 3 switch to allow different VLANs to exchange data outside their own broadcast domain.