VLAN connections in hardware, measured on the XGS 3300 and the XGS 136, 2026-10-24
Discovery 10 of the discoveries, taken from
the source to a product. The coprocessor's logical interface is a port and a VLAN together -
(iface_id << 12) | vlan - and each driver made only each port's VLAN 0. A tagged frame found no
entry, and the fast path handed it to the host without a lookup
(FROM_WIRE_TO_KN_LIF_UNKNOWN_VLAN_L3_MODE): every connection by a VLAN subinterface crossed the
host, on both appliances. Both drivers now give each VLAN subinterface of a front port its own
logical interface, name the VLAN in a next hop, and have the microflow write the tag
(OCTEP_BRCTL_ROUTED_VLAN, NPURPC_BRCTL_ROUTED_VLAN: the routed bridge control with its VLAN bit) -
added where a direction leaves by a VLAN, taken off where it arrives by one and leaves by a plain
port. A connection routed by a VLAN is now made in hardware like any other.
The whole page, with how it was taken and what it does not show: VLAN connections in hardware, measured on the XGS 3300 and the XGS 136, 2026-10-24.
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