User guide

Configuring Virtual Chassis Configuring Virtual Chassis
page 12-20 OmniSwitch AOS Release 7 Switch Management Guide March 2015
• Explicitly configuring the VFL and the physical port members is required. It’s recommended to config-
ure the VFL during network maintenance time or when the virtual chassis is first configured. Changing
the VFL configuration at runtime is supported but should be performed with caution as an incorrect
VFL configuration can cause undesirable disruption to traffic flows.
• It is recommended to configure the VFL at the same time as the chassis identifier. This ensures that the
switch reboots with the correct VFL configuration.
• For increased resiliency, there should be a minimum of two member ports and they should be distrib-
uted across different port groups and NI modules.
• Only physical ports operating at 10-Gbps (not including 10GBaseT) or 40-Gbps can be members of a
VFL. Additionally, 10-Gbps and 40-Gbps links cannot be mixed in the same VFL. Any type of 10Gbps
or 40-Gbps transceiver or direct-attached cable can be used for creating the VFL. 10GBase-T ports
cannot be members of a VFL.
• The member ports configured as part of the VFL are bundled to form a single logical link. All the
member ports must operate at the same speed.
• To help avoid a split chassis scenario the last active VFL member port cannot be deleted or disabled.
Additionally, the last NI module hosting the last active member port cannot be administratively
powered down or reloaded.
• The VFL automatically becomes a member of all VLANs configured on the switch.
• VFL member ports can only be configured on interfaces that are fixed ports, network ports or PFC
enabled ports. For instance, interfaces configured as Q-tag ports or ERP ports cannot be configured as
VFL member ports.
• The hello interval parameter must match between switches. The hello protocol runs across the VFL
between the switches.
• Some user-data traffic loss may be seen on VFL link when sending at wire rate. Since all packets that
traverse the VFL have an additional 16 byte header prepended to the packet this reduces the effective
bandwidth of a given VFL port.
For more information on Virtual Fabric Link, see “Creating the Virtual Fabric Link (VFL)” on page 12-21
Control VLAN
• The control VLAN is a reserved VLAN used for transporting control packets among the switches
comprising the virtual chassis.
• Runtime configuration changes to the control VLAN will only take effect after the next reboot of the
switch.
• The control VLAN must be the same between the switches comprising the virtual chassis.
For more information on the Control VLAN, see “Configuring the Control VLAN” on page 12-22
Configuring the Chassis Identifier
To configure the Virtual Chassis feature, a unique chassis identifier must first be assigned to each of the
switches that will form the Virtual Chassis group. Assigning the chassis identifier also enables the config-
uration of the additional virtual chassis parameters for the switch.