User guide

Automatic Fabric Overview Configuring Automatic Fabric
page 14-12 OmniSwitch AOS Release 7 Switch Management Guide March 2015
• The VLAN tag value is based on the Automatic Fabric setting for an SPB SAP profile. There are two
types of SPB SAP profiles available: single service and auto VLAN.
– The single service profile is used to create a SAP for untagged traffic received on a UNP SPB
access port.
– The auto VLAN profile is used to create a SAP for each VLAN ID tag received on the UNP SPB
access port.
• The SPB I-SID and BVLAN ID value for the SAP is based on an internal calculation performed by the
switch.
In this scenario, traffic arrives on the UNP SPB access port and triggers the switch to dynamically create a
“System Default” service profile. Then, based on the Automatic Fabric default SPB SAP profile setting
(single service or auto VLAN), the traffic received is examined to define the SAP that is dynamically
created to bind the traffic to an SPB service. The SPB service associated with the dynamic SAP is
identified through the I-SID and BVLAN values derived.
Loopback Detection
A provider network with a set of multiple switches interconnected together can be logically viewed as a
large single switch. The large single switch provides service access points to customer networks.
Configuration faults in customer networks can result in loops spanning both provider and customer
networks. This can result in broadcast storms. In order to protect a provider network from broadcast
storms, loops that involve SAP ports need to be detected and broken.
The LBD can detect and break loops created on SAP interfaces. For a SAP the LBD can be enabled for a
specific port or link aggregate that is assigned to the SAP. LBD for SAPs allows shutting down only the
specific interface (port or link aggregate) of the link involved in the loop.
Automatic Fabric supports loopback detection on SAP interfaces. Dual-homed connections can be done
through link aggregate connections to two or more devices that are part of the same VC. If a switch is
connected to multiple devices that are not part of the same VC, the port is converted to an access port and
a loop detection protocol will be run on these ports.
The status of LBD is configurable through Automatic Fabric commands and applied to the dynamically
created SAPs resulting from SPB discovery and configuration.
MVRP Discovery
MVRP is enabled globally after link aggregates are formed and SPB configuration exchange is completed
between peer devices.
• MVRP will operate and accept VLAN registrations on all Automatic Fabric ports and link aggregates
that are up. However, if LACP is stopped on a port for any reason, MVRP will not operate on that port.
• If a port or link aggregate goes down, any MVRP configuration is removed from the port or link
aggregate.
• MVRP is not enabled on ports that were configured as UNP SPB access ports during the SPB
discovery process.
Note. MVRP is supported only when the switch is operating in the flat Spanning Tree mode. If the switch is
running in the per-VLAN (1x1) mode when Automatic Fabric discovery is started for MVRP, the Spanning
Tree mode is automatically changed to the flat mode.