User guide

Configuring Automatic Fabric Automatic Fabric Overview
OmniSwitch AOS Release 7 Switch Management Guide March 2015 page 14-11
• LACP automatic discovery will work between a configured switch and an automatic discovery enabled
switch. The automatic discovery switch analyzes the LACP PDUs received from the configured
switch. In this scenario, an automatic discovery switch will place all of the ports from the same switch
with the same remote admin key into the same link aggregate.
• LACP link aggregates are configurable between any two automatic discovery switches by exchanging
custom LLDP PDUs with TLVs specific to the OmniSwitch. This exchange is necessary to determine
an admin key that both devices will use later for actual LACP communication. This exchange will also
determine the possible ports that can be part of a link aggregate. This is used only when LACP
discovery fails on the port.
SPB Discovery
After the LACP discovery phase has completed, the SPB discovery phase starts on the Automatic Fabric
ports. The main purpose of the SPB discovery phase is to configure the switch with the ability to
participate in an SPB backbone configuration. In addition to discovering SPB adjacencies and configuring
UNP SPB access ports, the following SPB elements are configured on the switch:
• BVLANs 4000-4015 are created and mapped to Equal Cost Tree (ECT) IDs 1-16, respectively.
• BVLAN 4000 will serve as the control BVLAN on which ISIS-SPB Hello packets are sent.
• Bridge priority is set to 0x8000.
During this phase all the Automatic Fabric ports are treated as network ports (SPB interfaces) on which
the discovery of SPB adjacencies is attempted. If at least one SPB adjacency is established on the switch,
UNP SPB access port configuration is attempted on ports or link aggregates that were not used to form
SPB adjacencies. Once configuration is finalized and traffic is received on the UNP SPB access ports, the
access port configuration is retained even if an adjacency goes down.
Dynamic Service Access Points (SAPs)
A SAP is a logical service entity that is configured on a switch to bind a service access port and traffic
received on that port to an SPB service ID. During Automatic Fabric discovery of SPB, ports may get
converted to UNP SPB access ports. This is done because UNP supports dynamically creating SPB service
profiles and corresponding SAPs for traffic received on UNP access ports.
The UNP feature supports SPB service profiles. This type of profile triggers the dynamic creation of a
SAP when traffic received on a UNP SPB access port is classified and assigned to that profile. A user-
defined SPB service profile specifies the following attributes that are used to dynamically create the SAP:
• The VLAN tag combined with the local UNP access port specifies the encapsulation value for the
SAP. For example, “1/1/2:50” specifies that traffic received on access port 1/1/2 tagged with VLAN 50
is mapped to the SAP for encapsulation and tunneling through the SPB backbone.
• The SPB service instance identifier (I-SID) and BVLAN ID specify the SPB service for the SAP that
will forward the encapsulated traffic through the SPB backbone.
To further automate this process, UNP also supports dynamically creating a “System Default” service
profile for traffic received on UNP SPB access ports that is not classified into a user-defined UNP service
profile. This is the case with traffic received on ports converted to UNP SPB access ports during the SPB
discovery process. The attribute values that a “System Default” SPB service profile uses to dynamically
create a SAP are derived as follows: