Tunnel Mode; 802.1Q Trunk Mode - Lenovo CN4093 Application Manual

Tunnel Mode

802.1Q Trunk Mode

344
CN4093 Application Guide for N/OS 8.3
In tunnel mode, a vPort can belong to only one VLAN. An outer tag with the
vPort's VLAN ID is inserted in packets that egress the vPort. The inner VLAN tag
remains unchanged. The switch processes packets based on the outer tag. When all
the ports or vPorts that belong to a particular VLAN are placed in tunnel mode,
they belong to one pass-through domain.
Use tunnel mode to send all VM data traffic to an upstream switch, for Layer 2 or
Layer 3 processing, in one domain. In such cases, the UFP port or vPort must be in
tunnel mode and the upstream switch port must be in 802.1Q trunk mode.
Note: Two vPorts on a physical port cannot be members of the same VLAN.
Figure 38. Packet pass-through in Tunnel Mode
Server
OS/Hypervisor
Regular
NIC attaches UFP
VLAN ID
Channel VLAN ID
Outbound
Packet
Outer tag sets vNIC;
NIC strips outer tag
Inbound
Packet
In trunk mode, a vPort can carry packets that have inner tags that belong to up to
1024 VLANs. When UFP is enabled, the following 9 VLANs are reserved for UFP
operation: 1 and 4002-4009. Each VLAN in the inner tag requires a VLAN
translation entry.
Note: Two vPorts operating in trunk mode on the same physical port cannot carry
the same set of VLANs in the inner tag.
Figure 39. Packet passing through in Trunk Mode
Server
OS/Hypervisor
Regular
NIC attaches UFP
VLAN IDs
Channel VLAN ID
Outbound
Packet
vNICs vPorts
NIC
Switching uses outer tag;
Ignores regular VLAN
Switching uses outer tag;
Ignores regular VLAN
vNIC vPort
NIC
VLAN
Translation
Lenovo Switch Ports without
Switch strips
outer tag
Switch adds outer
Channel VLAN ID
Lenovo Switch Ports without
VLAN
Switch strips
Classification
outer tag
vNICs
vNICs