The mighty cloud draws businesses and developers who seek its agility and productivity. But which type of cloud is best? We moved eBay Marketplace, a major eCommerce site, from a traditional infrastructure to a cloud model. We will present the strategic, technical and cost factors we weighed when deciding between cloud versus automation, and porting applications versus rewriting them. We will explain why we ended up with a hybrid: developing our own internal cloud while leveraging the massive infrastructure of public cloud providers.

3. 200M live listings
22B page views/day
9 Pb of data
6,000 application servers
250M queries/day
94M active users
23M SLOC
$62B 2010 gross merchandise volume 75B database calls/day

4. Beta
PCI
Compliant PCI
Compliant
Production
Research
Skunkworks
QA

7. DR
Number of servers required based on utilization for 8 pools

8. Even at 4x the
internal cost, public Cloud cost to
cloud would save Internal cost
money ratio
Internal cost is dominant
External cost is dominant

9. ?
Private Public
Hybrid
Build Buy
Build + OSS

11. Service Catalog REST APIs
Ticket driven run book Model driven close loop
automation automation
Configuration Management
Distributed state Management
Database (CMDB)
Chargeback Pay as you go
Multitenant infrastructure with
Server Virtualization
secure isolation

12. Cannot be
The task requires human involvement (e.g. racking and wiring)
automated
No support for
Component lacks API or requires UI based actions (e.g. checkpoint)
automation
Limited rate of
Configuration requires restart, reload, file sync (e.g. Bind, ISC DHCP)
change
No permission Configuration requires special credential/role (e.g. firewall, network)

14. Application App App App
Application App App App
Spare spare spare spare
Global resource pool
Infra Infra Infra Infra
Shared infrastructure

15. request order receive & deliver
{nb servers, rack & wire
model, app } Label (app)
“several”
1w weeks
2-3 w
repurpose
request order Receive deliver to request deliver
{nb servers, pre-racked cache {nb servers,
model } Pre-wired model, app }
quarterly
45 min
1 day
2-3 w
repurpose

16. IaaS/PaaS API IaaS/PaaS API
Resource Distributed Resource Distributed
orchestration orchestration
Allocation State Allocation State
Application Access Point Application Access Point
AuthN/AuthZ AuthN/AuthZ
Controller Controller Controller Controller
Compute Cluster Pool Compute Cluster Pool
Controller Controller Controller Controller Controller Controller
Compute Mgt. DNS Mgt.
LB
Mgt.
Monitoring Open Source
Solution
Network Prov Image/Pkg Repo Software Dist.
(openstack / Cloudstack)