Users Guide

In a single SFS domain, there is only one Master switch at any given time, and the rest of the leaf switches are designated as
the backup. A new Master is elected from the backup switches when the Master fails to provide high-availability to the fabric.
NOTE: Spine switches cannot be elected as a Master node within SFS.
Master advertisement
Once a Master is elected, it initiates all applications to automatically build the network fabric. The Master VIP is advertised using
mDNS Avahi services for applications to automatically discover the fabric through inband networks.
SFS REST services
The SFS REST service is started on the Master node. Applications consuming or integrating with SFS use this REST service for
fabric operations. Communication is performed with the fabric using the IPv6 VIP assigned to the SFS Master, or using the IPv4
out-of-band Management IP of the Master.
A default REST_USER account is created to authenticate all REST queries. The default password is admin, and Dell
Technologies recommends changing the password through VxRail Manager or OMNI.
NOTE: OMNI communicates with SmartFabric REST Services through REST_USER account only.
Master high availability
SFS uses an internal distributed data store where all fabric configuration is saved. This data is synchronized with all backup
switches ensuring the Master, and the backup switches always have the same view of the fabric. With a Master failover, the
switch taking over as the Master uses its internal data store to continue fabric operations.
When the fabric is expanded, the newly added switches receive all fabric policies from the SFS Master, once the switches are
added to the domain.
Preferred Master
When a Master is elected for a fabric, the switches that are configured as Preferred Master have a higher priority to become
the Master switch. If none of the switches are configured as the Preferred Master, any leaf switch can become the Master.
When the fabric is expanded, newly added switches may come up and form a fabric among themselves, and elect a Master
before they are connected to the existing fabric. When the new fabric merges with the existing fabric, SmartFabric elects a new
Master switch for the combined fabric. If one of the new leaf switches becomes the master, it may overwrite the configuration
in the existing fabric. Ensure that the leaf nodes in the existing fabric are set as the Preferred Master before expanding the
fabric to prevent the configuration loss.
NOTE:
When an uplink is created from SFS UI, preferred master is automatically set. If the uplink is not created using SFS
UI, when an uplink is created from OMNI, OMNI sets Preferred Master flag automatically on all configured leaf switches in
the fabric if not configured already.
SmartFabric or SFS domain
SmartFabric or SFS domain is interchangeable terminology, and the fabric consists of all switches directly connected to form
a single logical network. The L3 fabric is automatically assigned ID 100 and this ID cannot be changed. The fabric name and
description are automatically assigned, but can be changed through the SFS user interface.
Rack or VLT fabrics
When two leaf switches are discovered on specified VLTi ports, a VLT is automatically created between the two switches to
form a network fabric called the VLT fabric. This VLT fabric is automatically assigned with a fabric ID, a universally unique
identifier (UUID).
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SmartFabric Services