Dell Force10 S55T S55 Configuration Guide FTOS 8.3.5.3 - Page 537

Private VLANs, Private VLAN Concepts

Page 537 highlights

29 Private VLANs c s FTOS 7.8.1.0 adds a Private VLAN (PVLAN) feature for the C-Series and S-Series: For syntax details on the commands discussed in this chapter, see the Private VLANs Commands chapter in the FTOS Command Reference. This chapter contains the following major sections: • Private VLAN Concepts on page 537 • Private VLAN Commands on page 539 • Private VLAN Configuration Task List on page 539 • Private VLAN Configuration Example on page 543 • Inspecting the Private VLAN Configuration on page 544 Private VLANs extend the 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 is has one or more ports that are also isolated from each other. Private VLAN Concepts The VLAN types in a private VLAN (PVLAN) include: Community VLAN - A community VLAN is a type of secondary VLAN in a primary VLAN: • Ports in a community VLAN can communicate with each other. • Ports in a community VLAN can communicate with all promiscuous ports in the primary VLAN. Private VLANs | 537

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Private VLANs
|
537
29
Private VLANs
FTOS 7.8.1.0 adds a Private VLAN (PVLAN) feature for the C-Series and S-Series:
c s
For syntax details on the commands discussed in this chapter, see the Private VLANs Commands chapter
in the
FTOS Command Reference
.
This chapter contains the following major sections:
Private VLAN Concepts on page 537
Private VLAN Commands on page 539
Private VLAN Configuration Task List on page 539
Private VLAN Configuration Example on page 543
Inspecting the Private VLAN Configuration on page 544
Private VLANs extend the 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 serv-
ers could communicate with each other, and would be isolated from other customers. Another cus-
tomer might have another set of servers in another community VLAN. Another customer might want
an isolated VLAN, which is has one or more ports that are also isolated from each other.
Private VLAN Concepts
The VLAN types in a private VLAN (PVLAN) include:
Community VLAN
— A
community VLAN
is a type of secondary VLAN in a primary VLAN:
Ports in a community VLAN can communicate with each other.
Ports in a community VLAN can communicate with all promiscuous ports in the primary VLAN.