Users Guide

In a single rack deployment, VLT fabric shows two leaf switches and network fabric shows all the switches. The rack has a
network fabric and the VLT fabric represent the same set of switches. In a multi rack deployment, each rack has a VLT fabric,
and all the VLT fabrics and the spine switches together form the network fabric.
Default fabric settings
SFS automatically builds the network fabric using industry-standard Layer 2 and Layer 3 protocols.
Reserved VLANs
To build fabric, SFS reserves VLANs 4000 to 4094 for internal use. You are not allowed to use these VLANs for general use.
● VLAN 4000 — SFS control VLAN SFS automatically configures VLAN 4000 on all switches that are discovered in the
fabric, and uses it for all fabric operations internally. When a leaf or spine is switch is discovered, the ICL or ISL ports are
automatically added as tagged members.
● VLAN 4001 to 4079 — Leaf and Spine connections SFS automatically sets up the leaf and spine network configuration
using eBGP as the underlay routing protocol. SFS uses the reserved VLAN range (4001 to 4079) with automatic IP
addressing to set up the peer connections. When a spine switch is connected to the fabric, an ISL is created between
the leaf and spine switch. Each ISL link uses a reserved VLAN and the ISL ports that are configured to be the untagged
members of this VLAN. IP addresses from the reserved range are used for this VLAN, and an eBGP session is started on the
VLAN IP interface.
● VLAN 4080 — Global untagged VXLAN VLAN SFS automatically sets up VXLAN overlay networks with EVPN to extend
networks between racks in a multi rack deployment. SmartFabric OS10 requires an untagged VLAN on leaf switches for
VXLAN traffic handling when using VLT. VLAN 4080 with automatic IP addresses from the reserved range is used for
leaf-to-leaf interconnect (ICL) links.
● VLAN 4089 — OS10 internal use In SmartFabric mode, VLAN 4089 is the default VLAN and is reserved for OS10 internal
use.
● VLAN 4090 — iBGP peering between leaf switches SFS automatically sets up iBGP peering between a pair of leaf
switches directly connected over ICL links. VLAN 4090 with automatic IP addresses from the reserved range is used for
enabling iBGP sessions between the VLT peer switches.
● VLAN 4094 — VLT control VLAN SFS automatically creates VLAN 4094 on all leaf switches. VLAN 4094 is used for all
VLT control traffic between two VLT peer switches. VLAN 4094 is only added on the VLT interconnect links (ICL ports) on
leaf switches.
Reserved networks
SFS uses the 172.16.0.0/16 and 172.30.0.0/16 networks internally for the leaf and spine network configuration. If these networks
conflict with any networks in customer deployment, these default networks may be changed in the SFS UI using Edit Default
Fabric Settings. For complete information about SFS UI, see Dell EMC SmartFabric OS10User Guide available in Dell EMC
Networking OS10 Info Hub.
NOTE:
OMNI uses a docker instance with the default IP address of 172.16.0.1/16. Change the docker private network
configuration if the docker IP address conflicts with an existing customer deployment network, see Configure docker
private network.
Default client management network
SFS automatically sets up an overlay network that is called a client management network. When a device is automatically
onboarded on to the network fabric, the device uses the VLAN mapped to this overlay network. This network is a native VLAN
unless there is a policy specifying a different native VLAN. VLAN 4091 is used as the default client management VLAN for this
VXLAN network.
NOTE: The embedded SFS user interface allows you to change this VLAN to a specified VLAN.
SmartFabric Services 13