Dell Force10 MXL Blade MXL 10/40GbE Switch IO Module Configuration Guide - Page 393

22 Private VLANs (PVLAN) For syntax details about the commands described in this chapter, refer to the Private VLANs (PVLAN) Commands chapter in the FTOS Command Reference Guide. This chapter contains the following sections: • Private VLAN Concepts • Private VLAN Commands • Private VLAN Configuration Task List • Private VLAN Configuration Example • Inspecting the Private VLAN Configuration Private VLANs (PVLANs) extend the Dell Force10 operating software (FTOS) security suite by providing Layer 2 isolation between ports within the same VLAN. A private VLAN partitions a traditional VLAN into subdomains identified by a primary and secondary VLAN pair. Private VLANs block all traffic to isolated ports except traffic from promiscuous ports. Traffic received from an isolated port is forwarded only to promiscuous ports or trunk ports. Example uses of PVLANs: • A hotel can use an isolated VLAN in a private VLAN to provide internet access for its guests, while stopping direct access between the guest ports. • A service provider can provide Layer 2 security for customers and use the IP addresses more efficiently by using a separate community VLAN per customer, while at the same time using the same IP subnet address space for all community and isolated VLANs mapped to the same primary VLAN. In more detail, community VLANs are especially useful in the service provider environment because multiple customers are likely to maintain servers that must be strictly separated in customer-specific groups. A set of servers owned by a customer could comprise a community VLAN, so that those servers could communicate with each other, and would be isolated from other customers. Another customer might have another set of servers in another community VLAN. Another customer might want an isolated VLAN, which has one or more ports that are also isolated from each other. Private VLANs (PVLAN) | 391