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vlan(7)


NAME

  vlan, VLAN - Virtual LAN (VLAN) introductory information


DESCRIPTION

  A Virtual Local Area Network (VLAN) provides administrators with the
  ability to create logical groups of systems that can communicate as if they
  were on the same LAN. Multiple VLANs can exist on the same physical
  network. Traffic between VLANs is restricted. Bridges forward all traffic,
  including broadcast traffic, only to LAN segments that serve the VLAN to
  which the  traffic belongs.

  A VLAN is identified by a VLAN ID, which is contained in a special Ethernet
  frame called a tagged frame. This tagging format is defined in the IEEE
  802.1q standard.

  VLAN requires an optional kernel subsystem (vlan.mod). You can verify the
  presence of the VLAN subsystem by issuing the sysconfig -s vlan command. If
  the vlan subsystem is not loaded, you can load it using either of the
  following methods:

    ·  Dynamically load it using the sysconfig -c vlan command.

    ·  Run the vlanconfig command. This loads vlan.mod if it is not present
       in the kernel.

  After the subsystem is loaded, you can configure a VLAN.

  VLAN Configuration

  You can configure VLANs either in multiuser mode or at boot time with the
  vlanconfig command. When you configure a VLAN, you specify the virtual
  interface name (vlanx), the lower interface on which the VLAN virtual
  interface is configured, and a VLAN ID. This enables the lower interface to
  participate in the VLAN identified by the VLAN ID. You can enable an
  interface to participate in multiple VLANs by creating multiple virtual
  interfaces on it. The total number of VLAN virtual interfaces is limited
  only by system resources.

  After you create a VLAN virtual interface, you manage it like any interface
  by using the ifconfig command (for example, to configure IP addresses).

  After an interface is configured for VLAN, all frames received on that
  interface are either enqueued to a VLAN virtual interface, or dropped. If
  the received frame is an IEEE 802.1q tagged frame, the VLAN ID is extracted
  and the frame is delivered to the VLAN virtual interface with the same VLAN
  ID or is dropped if none is found. If the frame is not a tagged frame (that
  is, typical Ethernet traffic), it is delivered to the untagged VLAN virtual
  interface, or dropped if the untagged interface is not found. (See
  vlanconfig(8) for more information.) This provides maximum flexibility to
  the system manager in establishing a VLAN environment.

  Packets sent from a VLAN virtual interface are encapsulated in tagged
  frames that include their VLAN ID. Packets sent from an untagged VLAN
  virtual interface are sent as untagged frames. Interfaces that are enabled
  for tagged frames must be connected to LAN segments, or directly to
  switches, that support IEEE 802.1q tagging. A switch's VLAN configuration
  must be done manually.

  VLAN and NetRAIN

  You can enable NetRAIN virtual interfaces (nr) for VLANs provided the
  physical adapters that make up the NetRAIN set adhere to the restrictions
  in the "Restrictions" section. Each adapter in the NetRAIN set must be
  connected to a switch port that is configured into the same set of VLANs as
  the NetRAIN virtual interface. You cannot configure VLAN virtual interfaces
  into a NetRAIN set.

  VLAN and Link Aggregation

  You can enable link aggregation group virtual interfaces (lag) for VLANs
  provided the physical adapters that make up the group adhere to the
  restrictions in the "Restrictions" section. Each adapter in the group must
  be connected to a switch port that is configured into the same set of VLANs
  as the link aggregation group virtual interface. You cannot configure VLAN
  virtual interfaces into a link aggregation group.


RESTRICTIONS

  The following restrictions apply:

    ·  Supports only Ethernet (802.3 CSMA/CD) links.

    ·  Supports only DEGPA (alt), DE60x (ee), DEGXA (bcm), and TULIP (tu)
       network interface cards (NICs).


SEE ALSO

  Commands: vlanconfig(8)

  System Attributes: sys_attrs_vlan(5)

  Files: inet.local(4)

  Technical Overview

  Network Administration: Connections

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