User guide

Configuring Automatic Fabric Interaction with Other Features
OmniSwitch AOS Release 7 Switch Management Guide March 2015 page 14-21
Interaction with Other Features
This section contains important information about how other OmniSwitch features interact with the
Automatic Fabric feature. Refer to the specific chapter for each feature to get more detailed information
about how to configure and use the feature.
System
When the Automatic Fabric feature is enabled there may be periodic changes to the switch configuration.
This will cause the Running Configuration to display as “NOT SYNCHRONIZED” even after manually
synchronizing CMMs.
LLDP
• LLDP has been enhanced to detect peer device ports connected on boot up using a proprietary TLV
and LLDP PDU exchanges. LLDP discovery will help to detect a set of ports connected to a neighbor
device so that a link aggregation can be formed on the detected set of ports if LACP negotiation
succeeds.
• If a port is brought up after Automatic Fabric has run and Automatic Fabric is enabled on that port,
LLDP exchanges are used to determine if the port is connected to the same device so that the already
connected port and subsequent new ports can form an aggregate.
LACP
An Automatic Fabric discovery switch will be able to learn and configure LACP link aggregates from any
802.3AD compliant and already configured switch.
• If an LACP frame is received on a non-aggregate port that has Automatic Fabric enabled, the
Automatic Fabric discovery window is started provided there are no SPB adjacencies and no MVRP
registrations on the port.
• If a neighbor device is manually configured for LACP with lesser ports than the number of connected
ports between devices, then the rest of the ports in an automatic discovery enabled device will join/
form a back up LACP configuration.
During the LACP discovery and configuration process, the following scenarios are handled:
• Neighbor is already configured with LACP—Linkagg will detect LACP PDUs on the ports and map
them to different neighbor devices based on admin key, system ID and priority received in the PDUs.
This allows an Automatic Fabric enabled port to join an already formed aggregate or a new aggregate
ID.
• Neighbor device is also booting up with this device (max aggregate size not exceeded)—If there
are fewer ports than the maximum possible size of an aggregate then all ports are chosen and an
aggregate is formed.
• Neighbor device is also booting up with this device (max aggregate size exceeded)—Connecting
more ports than is supported for a link aggregate is not supported. The number of physical connections
should not be greater than the maximum number of link aggregate ports supported for the OmniSwitch.
• Device is already up and new port comes up—In this case the device might already have a port/
aggregate which is connected to the same neighbor device, then the port joins the aggregate which is
already formed or both ports will form a new aggregate.