OpenFlow Data Center - A case Study by Pica8
- 1. 2/27/2014 OpenFlow Data Center A Case Study David.Liu@Pica8.com 1
- 2. Topics Pica8 Introduction Network design goals Constraints How to scale Key OpenFlow features Controller Network management Current status 2
- 4. White Box Platforms 4 Broadcom Fire Bolt & Triumph2 • 48 x 1G + 4 x 10G Broadcom Trident + • 48 x 10G + 4 x 40G Broadcom Trident 2 • 32 x 40G • 48 x 10G + 6 x 40G
- 5. Network Design Goals Green fields white box data center No legacy inside data center Floodless network Complete control over • IP addresses • Forwarding decisions, while and black lists • Topology • Controller architecture Maximum visibility 100% automation 5
- 6. Starting Constraints (4-2013) TCAM size, 1K – 2K entries based on model Fixed ASIC pipeline, not all OpenFlow features can fit No multiple table support • How to forward based on dl_src then set_queue without multiplying the number of rules No positive ack after flow_mod OpenFlow v 1.2 Group table/Select, ECMP & fast failover Zero touch provisioning Metering 6 Tunnel Termination L2/L3/MPLS TCAM/SRAM Ingress ACL Metering Switching Scheduling Modification Egress ACL
- 7. Scale under Constraints 7 ToR Aggre Core N x 10GN x 10G Scaling unit = 2 Core + 2 Aggregation + 12 Racks (2 ToR + 40 servers) N x 10G N x 10G N x 10G
- 8. ToR Rules 8 Drop Learning Forwarding Priority eth_type actions 50000 ipv6 actions=drop 50000 rarp actions=drop 50000 dl_type=0x8809 actions=drop 50000 dl_type=0x8100 actions=drop Priority eth_type match actions 40000 ip in_port=29 nw_src=100.0.0.29 actions=CONTROLLER:1024 40000 arp in_port=23 arp_spa=100.0.4 actions=CONTROLLER:1024 40000 ip in_port=36 nw_src=100.0.0.36 actions=CONTROLLER:1024 40000 ip in_port=48 nw_src=100.0.0.154 actions=CONTROLLER:1024 Priority eth_type match Actions 20000 ip in_port=48 nw_src=100.0.0.128/25 nw_dst=100.0.0.5 actions=set_field:00:11:90:9b:c8:38- >eth_dst, output:5 20000 ip nw_src=100.0.0.0/25 nw_dst=100.0.0.5 actions=set_field:00:11:90:9b:c8:38- >eth_dst, output:5 10000 ip in_port=49 nw_dst=100.0.0.5 actions=set_field:00:11:90:9b:c8:38- >eth_dst, output:5 10000 ip in_port=50 nw_dst=100.0.0.5 actions=set_field:00:11:90:9b:c8:38- >eth_dst, output:5 10000 ip in_port=51 nw_dst=100.0.0.5 actions=set_field:00:11:90:9b:c8:38- >eth_dst, output:5 10000 ip in_port=52 nw_dst=100.0.0.5 actions=set_field:00:11:90:9b:c8:38- >eth_dst, output:5 20 ip nw_src=100.0.0.5 nw_dst=100.0.0.0/8 actions=group:55 10 ip nw_src=100.0.0.5 actions=set_field:00:11:90:c8:bc:3e- >eth_dst,output:3
- 9. Aggregation Rules 9 Drop Forwarding Priority eth_type actions 50000 ipv6 actions=drop 50000 rarp actions=drop 50000 dl_type=0x8809 actions=drop 50000 dl_type=0x8100 actions=drop Priority eth_type match actions 40000 ip nw_dst=100.0.0.5 actions=group:53 40000 ip nw_dst=100.0.0.0/22 actions=group:55 40000 ip nw_dst=100.0.4.0/22 actions=group:58 30000 ip nw_dst=100.0.16.135 actions=group:10
- 10. Key Features TCAM optimization (2K, 4K, & 8K entries) Group Select / ECMP OpenFlow v1.3 Metering Pre-configured queuing Analytic DB Zero touch provisioning Configurable event reporting Switch inventory Cross flow mode 10 ToR Aggre Core N x 10GN x 10G
- 11. Cross Flow Mode 11 Openflow Network Legacy Network Crossflow - Local control off CrossFlow Local control on Legacy port TCAM FDB & Route Table
- 12. Controller 12 In house controller development Use a stripped down open source controller parser Less than 1 year development & ready for production Centralized or distributed In progress • OVS DB interface integration • Inventory • Event reporting New ideas on how a controller framework could be
- 13. Network Management SNMP ? If it is needed, should it be on the switch ? Or .. Inventory Event reporting Controller management 13
- 14. Conclusion 14 OpenFlow cannot solve all problems but fits well with some applications All OpenFlow application needs customization with domain knowledge, no off-the-shelves solution Scalability has to be designed Allow automation to save OPEX Controller is still the key to OpenFlow deployment