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IP Unnumbered Building Simplified, Automated and Scalable Data Center Networks with Overlays (VXLAN/FabricPath) BRKDCT-3378 Lukas Krattiger, Technical Marketing Engineer [email protected] @CCIE21921 Session Objectives • Focus on Data Center Networks and Fabrics with Overlays • Closer Look on Packet Encapsulation (VXLAN) – Underlay – the Transport for the Overlay – Control-Plane – Exchanging Information – Optimizing the Forwarding • Overview on Frame Encapsulation (FabricPath) – Similarities to Packet Encapsulation • Fabric Management & Automation approaches BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public Session Non-Objectives • Deep-Dive into FabricPath – There are many Sessions and Recordings • Comparison between different Orchestration and Management Tools • Automation Workflows or Services Catalogs BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 4 Who am I? • Born behind the Mountains • Other People call it Switzerland • Living in the land of E-Cars and Startups • Aka San Francisco Bay Area • Not sure if I’m 100% Human • US Immigration calls me “Legal Alien” • Dad, Husband, Geek BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public “We can NOT solve our Problems with the same Thinking we used when we Created them” Albert Einstein 6 Agenda • Data Center Fabric Properties • Optimized Networking with VXLAN – Overview – Underlay – Control & Data Plane – Multi-Tenancy • Optimized Networking with FabricPath • Fabric Management & Automation BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 7 Data Center “Fabric” Journey (Standalone) STP VPC FabricPath VXLAN MAN/WA N FabricPath VXLAN /BGP /EVPN MAN/WA MAN/WA N N BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public A Fork in the Road BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public Data Center Fabric Properties Data Center Fabric Properties Scale, Resiliency, Efficiency • Any subnet, anywhere, rapidly • Reduced Failure Domains • Extensible Scale & Resiliency • Profile Controlled Configuration Full Bi-Sectional Bandwidth (N Spines) Any/All Leaf Distributed Default Gateways Any/All Subnets on Any Leaf BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 11 Spine/Leaf Topologies Data Center Fabric Properties • High Bi-Sectional Bandwidth • Wide ECMP: Unicast or Multicast RR RR • Uniform Reachability, Deterministic Latency • High Redundancy: Node/Link Failure • Line rate, low latency, for all traffic BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 12 Variety of Fabric Sizes Data Center Fabric Properties • Fabric size: Hundreds to 10s of Thousands of 10G ports RR RR • Variety of Building Blocks: – Varying Size – Varying Capacity – Desired oversubscription – Modular and Fixed • Scale Out Architecture – Add compute, service, external connectivity as the demand grows BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 13 Variety of South-bound Topological Connectivity Data Center Fabric Properties • Flexible connectivity options to the Leaf nodes – FEX in straight-through or dual-active RR RR mode (eVPC) – Blade Switches – Hypervisors or bare-metal servers attached in vPC mode Virtual Switch BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 14 Data Center Fabric Properties Extended Namespace Scalable Layer-2 Domains Integrated Route and Bridge Hybrid Overlays Inter-Pod connectivity Multi-Tenancy BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 15 Optimized Networks with VXLAN Overview Classic Ethernet IEEE 802.1Q Frame Format Classic Ethernet • Traditionally VLAN is expressed DMAC SMAC 802.1Q Etype Payload CRC over 12 bits (802.1Q tag) Frame – Limits the maximum number of segments in a Data Center to 4096 Destination MAC (DMAC) VLANs Source MAC (SMAC) TPID TCI 4 bytes 802.1Q 0x8100 PCP CFI VID (16 bits) (3 bits) (1 bits) (12 bits) Ether Type (Etype) Data (Payload) CRC/FCS VLAN ID 12 bits TPID = Tag Protocol Identifier, TCI = Tag Control Information, PCP = Priority Code Point, CFI BRKDCT= Canonical-3378 Format© 2015 CiscoIndicator, and/or its VIDaffiliates. = AllVLAN rights reserved. Identifier Cisco Public 17 Overview FabricPath Encapsulation and Frame Format Classic Ethernet • Cisco FabricPath introduces Classic DMAC SMAC 802.1Q Etype Payload CRC Ethernet Frame Encapsulation by Frame adding 16 bytes • Traditionally VLAN, expressed over 16 bytes IEEE 802.1Q tag, stays the same Cisco Outer Outer FP CRC DA SA Tag DMAC SMAC 802.1Q Etype Payload FabricPath (new) Frame (48) (48) (32) BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 18 Overview Introducing FabricPath w/Segment-ID (1) Classic Ethernet • Cisco FabricPath introduces Classic DMAC SMAC 802.1Q Etype Payload CRC Ethernet Frame Encapsulation by Frame adding 16 bytes • Traditionally VLAN, expressed over 16 bytes IEEE 802.1Q tag, stays the same Cisco Outer Outer FP FabricPath+Segm Segment CRC DMAC SMAC Etype Payload DA SA Tag ID ent-ID (48) (48) (32) (new) Frame • FabricPath w/Segment-ID leverages a two 802.1Q tags for a total address space of 24 bits 802.1Q VLAN ID (12 bits) Segment-ID 24 bits – Support of ~16M segments 802.1Q VLAN ID (12 bits) TPIDBRKDCT 0x8100-3378 = VLAN© 2015 Tagged Cisco and/or Frame its affiliates. with All IEEErights reserved. 802.1Q /Cisco TPID Public 0x893B19 = TRILL Fine Grained Labeling Overview Introducing FabricFath w/Segment-ID (2) Classic Ethernet • Cisco FabricPath introduces Classic DMAC SMAC 802.1Q Etype Payload CRC Ethernet Frame Encapsulation by Frame adding 16 bytes • Traditionally VLAN, expressed over 16 bytes IEEE 802.1Q tag, stays the same Cisco Outer Outer FP FabricPath+Segm Segment CRC DMAC SMAC Etype Payload DA SA Tag ID ent-ID (48) (48) (32) (new) Frame • FabricPath w/Segment-ID leverages TCI outer TPID a double 802.1Q tag for a total 4 bytes 0x8100 PCP CFI VID 802.1Q (16 bits) (3 bits) (1 bit) (12 bits) address space of 24 bits Inner TPID TCI – Support of ~16M segments 4 bytes 0x893B PCP CFI VID 802.1Q (16 bits) (3 bits) (1 bit) (12 bits) TPIDBRKDCT 0x8100-3378 = VLAN© 2015 Tagged Cisco and/or Frame its affiliates. with All IEEErights reserved. 802.1Q /Cisco TPID Public 0x893B20 = TRILL Fine Grained Labeling Overview Introducing VXLAN • Traditionally VLAN is expressed over 12 bits (802.1Q tag) – Limits the maximum number of segments in a Data Center to 4096 VLANs Classical Ethernet Frame DMAC SMAC 802.1Q Etype Payload CRC • VXLAN leverages the VNI field with 50 bytes Original CE Frame Outer a total address space of 24 bits VXLAN IP UDP VxLAN 802.1Q CRC MAC DMAC SMAC Etype Payload (20) (8) (8) optional (new) Frame (14) – Support of ~16M segments Cisco DFA Frame 8 bits 24 bits 24 bits 8 bits • The VXLAN Network Identifier ags Reserved VNIVNI Reserved (VNI/VNID) is part of the VXLAN Header VNI BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 21 Next-Hop MAC Address Src VTEP MAC Address VXLAN Frame Format Dest. MAC Address 48 MAC-in-IP Encapsulation Src. MAC Address 48 VLAN Type 14 Bytes 16 IP Header 0x8100 (4 Bytes Optional) 72 Misc. Data VLAN ID 16 Tag Outer MAC Header Protocol 0x11 (UDP) 8 Ether Type 16 Header 0x0800 16 20 Bytes Checksum Source IP 32 Outer IP Header Src and Dst Underlay addresses of the Source 16 Dest. IP 32 VTEPs Port UDP Header VXLAN Port 16 Hash of the inner L2/L3/L4 headers of 8 Bytes the original frame. UDP Length 16 Enables entropy for ECMP Load balancing in the Network. VXLAN Header UDP 4789 Checksum 0x0000 16 50 (54) Bytes of Overhead of Bytes (54) 50 VXLAN Flags 8 RRRRIRRR Allows for 16M Original Layer-2 Frame Overlay possible Reserved 24 Segments 8 Bytes VNI 24 Reserved 8 BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 22 Optimized Networks with VXLAN Data Center Fabric Properties Extended Namespace Scalable Layer-2 Domains Integrated Route and Bridge Multi-Tenancy BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 23 Why VXLAN? VXLAN provides a Network with Segmentation, IP Mobility, and Scale • “Standards” based Overlay • Leverages Layer-3 ECMP – all links forwarding • Increased Name-Space to 16M identifier • Integration of Physical and Virtual • It’s SDN BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 24 VXLAN Taxonomy (1) Edge Device Edge Device Local LAN Local LAN IP Interface Segment Segment Physical Physical Host Edge Device Local LAN Host Segment Virtual Switch Virtual Hosts BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 25 VXLAN Taxonomy (2) VTEP VTEP V V Local LAN Local LAN Segment Segment Encapsulation Physical Physical Host VTEP V Local LAN Host Segment Virtual Switch VTEP – VXLAN Tunnel End-Point VNI/VNID – VXLAN Network Identifier Virtual Hosts BRKDCT-3378 © 2015 Cisco and/or its affiliates. All rights reserved. Cisco Public 26 Session Marketing Session ID Session Title Speaker Day / Time LTRDCT-1224 Implementing VXLAN in Datacenter Lilian Quan Tuesday, 9:30 Technical Marketing Engineer Wednesday, 9:00 BRKAPP-9004 Data Center Mobility, VXLAN & ACI Fabric Architecture Bradley Wong Tuesday, 11:15 Principal Engineer PNLDCT-2001 Panel: Overlays in the Data Center - A Customer Perspective Panel Tuesday, 4:45p BRKDCT-2328 Evolution of Network Overlays in Data Center Clouds Victor Moreno Wednesday, 11:30 Distinguished TME BRKDCT-2456 Building Multi-tenant DC using Cisco Nexus Switching Elyor Khakimov Wednesday, 2:30p Technical Marketing Engineer BRKDCT-2404 VXLAN deployment models - A practical perspective Victor Moreno Thursday, 9:00 Distinguished TME BRKACI-2001 Integration and Interoperation of existing Nexus networks into Mike Herbert Thursday, 11:30 an ACI architecture Principal Engineer BRKDCT-2049 Overlay Transport Virtualization Brian Farnham Thursday, 2:30p Technical Marketing Engineer BRKDCT-3378 © 2015 Cisco and/or its affiliates.
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