OcNOS 6.6.1 Maintenance
OcNOS 6.6.1 is a maintenance release of the OcNOS 6.6 branch, released on July 7, 2025. On OcNOS DC it adds Dynamic Load Balancing (DLB), PFC with QoS and DCBX over Layer 3 interfaces, ECN and ETS for AI and ML fabrics, and 800G grey and 800G ZR optics on supported platforms. On OcNOS SP it adds TI-LFA for IS-IS with Flex-Algo, L3VPN ECMP, policy-based routing with next-hop tracking and L2VPN to L3VPN stitching. The 6.6 branch life cycle applies: on sale until February 28, 2028 and supported until February 28, 2030.
Major additions in this release
AI fabric (OcNOS DC)
Dynamic Load Balancing (DLB), PFC with QoS over Layer 3 interfaces, DCBX LLDP capability for PFC over Layer 3, Explicit Congestion Notification (ECN) and Enhanced Transmission Selection (ETS) on supported platforms.
800G optics (OcNOS DC)
800G grey and 800G ZR QSFP-DD optics and 800G QSFP-DD port breakout on supported platforms.
Segment Routing (OcNOS SP)
TI-LFA for IS-IS with Flex-Algo, user-defined adjacency SIDs for IS-IS (RFC 8667) and SR-based micro-loop avoidance for IS-IS.
VPN services (OcNOS SP)
L3VPN ECMP for VPNv4 and VPNv6, L2VPN to L3VPN stitching, BVI support for VPNv4, VPNv6, 6PE and DHCP, and TWAMP over inter-VPN access interfaces.
Routing policy
Policy-based routing with next-hop tracking on OcNOS SP, and multiple BGP large communities in a route map on OcNOS SP and DC.
EVPN
MAC limits for EVPN MPLS on OcNOS SP and for EVPN-VXLAN on OcNOS SP and DC, and single-hop BFD over IRB on OcNOS DC.
Qualified platforms in this release
See the full Hardware Compatibility List for all qualified platforms. View HCL →
Deep dives, blogs, and press
Engineering perspectives and announcements that complement this release.