The Process of Selecting Data Center Sites at Dropbox

**Selecting the Perfect Data Center: Dropbox’s Approach**
For over a decade, Dropbox has been operating a world-class storage system, leveraging a multi-metro, hybrid-cloud architecture that spans the globe. But how did we come to this point? We had to learn what makes a good data center and how to choose the right location. In this article, we will delve into our data center site selection process, while emphasizing our focus on sustainability, cost, and reliability.

**Defining Resource Requirements**
Before we can select a new data center location, our capacity engineering team plays a crucial role in defining our resource requirements. They assess the services we need and quantify the necessary cabinet counts. Additionally, the datacenter engineering team focuses on three key requirements:

**1. Power**
We evaluate power based on historical and projected usage by existing and future equipment. This analysis is usually expressed in kW or MW allocation, encompassing the total expected IT load.

**2. Space**
To accommodate various configurations, we ensure there is adequate space to store and support cabinets, adhering to industry best practices such as 4-foot cold aisles and 6-foot hot aisles.

**3. Time**
We establish a target date for the capacity to be online and available, commonly known as the lease commencement date.

**The Search Process**
After determining our capacity requirements, we initiate the search for locations and data center facilities that can accommodate our needs. Leveraging our network of providers, we identify those active within the desired market. This initial outreach helps us gauge availability, alternative power thresholds, or timeline requirements. Based on the responses received and our flexibility with power, space, and time, we make decisions about advancing certain providers to the next stage.

**Issuing the RFP Document**
Following the initial responses, Dropbox issues a comprehensive Request for Proposal (RFP) document, which outlines our facility-level requirements. Key parameters we look for include:

**1. Supporting Infrastructure Design**
We adhere to the Uptime Institute’s guidelines for Tier III facility standards, ensuring best practices in cooling, power, maintenance activities, and fault tolerances. Any deviations are then evaluated for further consideration.

**2. Expected Cabinet Weight and Dimensions**
We assess the weight and dimensions of equipment to ensure the flooring system can support both moving the cabinets and their weight once deployed on the data center floor.

**3. Network Design**
At this stage, we prioritize understanding the ingress and egress of traffic and determining if our preferred carrier is available. We also explore options for nearby carriers and assess whether the connection can be delivered to our space with the desired level of redundancy.

**Prioritizing Sustainability with PUE**
In recent years, Dropbox has placed greater emphasis on power usage effectiveness (PUE) to promote sustainability. Additionally, we seek facilities that utilize renewable energy sources and implement efficiency practices. By requesting a lower PUE in our contract negotiations, we encourage environmentally-friendly initiatives such as the use of eco-friendly cooling units, strict adherence to hot and cold aisle separation, and proper airflow containment methods.

**Bid Leveling and Technical Questionnaire**
Once all RFP responses have been received, we conduct a bid leveling process to assess the cost of each proposal. During this process, we share a technical questionnaire that seeks detailed information on space, power design, cooling design, network design, historical data, site environmental risks, security measures, and operational specifics. This questionnaire helps us identify potential gaps or unique features within each offer.

**Unveiling Potential Issues**
The answers to our questionnaire have allowed us to uncover potential issues, including:

**1. Reduced UPS Redundancy**
We encountered a provider that offered only 30 seconds of emergency power in the event of a power outage due to using an inertia wheel, instead of the standard UPS setup that provides five minutes. Such situations emphasize the importance of a quick generator startup during utility failure events.

**2. Increased Risk from Construction Delays**
Construction delays pose a considerable risk in meeting deadlines. If the power availability date aligns closely with the required date, any delay in construction could hinder operations.

**3. Inadequate Monitoring Programs**
Facilities lacking automated alerting systems for critical alerts may introduce delays or errors in our response. As part of our selection process, we prioritize facilities that have advanced monitoring capabilities.

**On-Site Validation**
After completing the questionnaires, we narrow down our choices to 4-6 providers who appear to be commercially and technically viable. We then conduct site walk evaluations to validate these providers in person. By physically assessing the facilities, we can confirm the accuracy of the information provided in the questionnaire. This step has helped us identify potential gaps or issues that would have gone unnoticed without an on-site visit.

In conclusion, Dropbox’s data center site selection process involves defining resource requirements, conducting extensive evaluations, prioritizing sustainability, and validating providers on-site. By striking a balance between cost, reliability, and our company values, we have successfully negotiated favorable rates and reliability in our last three selection processes. Whether you are a data center expert or new to the process, we hope this insight into our approach is beneficial for your search.