User guide

Configuring Virtual Chassis Virtual Chassis Overview
OmniSwitch AOS Release 8 Switch Management Guide May 2014 page 13-7
Slave Chassis - Any chassis which is not the Master chassis is considered a Slave chassis. A Slave chas-
sis is not directly configured, it communicates with the Master chassis through the virtual-fabric links to
determine its configuration. The VC LED will be amber.
Virtual Chassis EMP Address - The Virtual Chassis management IP address (EMP-VC). This is a
configurable IP address that is automatically assigned to the current primary chassis management module
(CMM) of the master chassis. This parameter is stored in the vcboot.cfg configuration file.
Chassis EMP Address - The local chassis management IP address (EMP-CHAS1). This is a configurable
IP address that is automatically assigned to the primary chassis management module (CMM) of the local
chassis regardless of its master or slave role. This parameter is stored in the chassis specific vcsetup.cfg
configuration file.
Virtual Fabric Link (VFL) - Dedicated ports that connect the chassis participating in the Virtual Chas-
sis. As one of the basic building blocks of a Virtual Chassis configuration, the VFL facilitates the flow of
traffic and the transfer of control data between the Master and Slave chassis.
Control VLAN - A special type of VLAN reserved for the inter-chassis communication exchange
between the switches participating in a Virtual Chassis. Only VFL ports are assigned to this VLAN, and
no other ports are allowed to join the Control VLAN.
IS-IS VC - Proprietary protocol for managing a Virtual Chassis topology. This protocol has no interac-
tion with IS-IS routing or IS-IS SPB protocols. Responsible for information exchange with peers over the
VFL, determining adjacencies, loop-detection and the shortest path between members of the VC.
VCSP - Virtual Chassis Split Protection. A proprietary protocol used by VC to detect and protect against
network disruption when a VC splits.
vcsetup.cfg - A file containing information pertaining to the current physical switches, helping incorpo-
rate it into a virtual chassis. This file contains information such as Chassis ID, Group ID, Chassis priority,
control VLAN, and chassis EMP IP addresses.
vcboot.cfg - A file containing information pertaining to the virtual chassis as a whole including L2 and L3
configuration, management configuration, user ports configuration, etc.
Virtual Chassis - Boot-Up
The Master chassis contains the vcboot.cfg file that contains the configuration for the entire virtual chas-
sis. All the switches (i.e. the one that will eventually become the Master and the ones that will become
Slaves) contain a vcsetup.cfg file that allows them to establish an connection over a VFL to all the other
neighboring chassis.
1 Upon boot-up, a switch will read its local vcsetup.cfg file and attempt to connect to the other neighbor
switches.
2 Upon connection, the switches will exchange the parameters configured in their local vcsetup.cfg files.
3 As a result of this exchange, they will discover the topology, elect a Master based on criteria described
in the next section, start periodic health checks over the VFL and synchronize their configuration as
defined within the vcboot.cfg configuration file.
4 All Slaves, if they do not have a local copy of vcboot.cfg, or their local copy does not match the copy
found on the Master, will download their complete vcboot.cfg from the Master chassis and reboot using
this copy of vcboot.cfg as its configuration file.