Production Deployment

The Ed-Fi ODS / API supports a wide variety of deployment models, including on-premises and cloud-based deployments, virtualized deployments, load-balanced deployments, and so on.

This section of the documentation covers the key concepts API platform hosts should understand before deploying to a production environment, along with details about specific configurations.

Production System Components

There are several websites and databases that work together to provide primary and supporting functions for a Production instance:

• Websites

  • Ed-Fi ODS API. The REST endpoint for client applications.

  • Security Configuration Websites. These websites provide administrative tools for managing API client keys and secrets.

• Databases

  • EdFi_ODS. A database that stores data for the Ed-Fi ODS / API.

  • EdFi_Admin. A database containing authentication information for API clients.

  • EdFi_Security. A database containing authorization information for API clients.

  • EdFi_Bulk. A database containing bulk operation storage.

• Services

  • Upload Worker. The windows service that joins uploaded bulk data for the Bulk Load API.

  • Bulk Worker. The windows service that loads bulk data for the Bulk Load API.

Of particular note: production deployments should not include the Swagger Documentation UI, Sandbox Administration UI or the EdFi_ODS_* databases. Those components are included by default in the code distribution – and are appropriate for a Sandbox instance of the ODS / API – but should not be deployed to production.

Configuration

Beyond changes to database connection strings, the Ed-Fi ODS / API is configurable using Microsoft OWIN startup classes. Several "off-the-shelf” startup classes representing common deployment configurations are provided in the EdFi.Ods.Api project in the Startup namespace. These do not represent the full extent of customization available.

Most implementations will extend one of the provided Startup classes (StartupBase, SandboxStartup, SharedInstanceStartup, and YearSpecificStartup) and reference the new startup class in the owin:appStartup application setting in the Web.config file.

Changes to the processing pipelines, caching mechanisms, data repository, and many other considerations can be adapted by changing the Castle Windsor registrations called from the OWIN startup class when the website is loaded.

Planning for a Secure Production Deployment

The security of student information is a primary concern of any API platform host. This section outlines considerations for platform hosts when planning Ed-Fi ODS / API deployments.

The information in this section can be used as a checklist or as input into a threat modeling exercise during the deployment planning cycle.

Value Assets

A list of high-value assets and a brief description of each follow:

The following are recommendations and precautions for implementers to consider when planning a production deployment.

An obvious disclaimer applies: these are just general guidelines offered in summary form. Platform hosts should include trained security professionals in their deployment planning and conduct security audits prior to deployment – and periodically thereafter.

Recommendations for the API

• Ensure that only intended client applications can interact with the Ed-Fi ODS / API.

• Implement a process for client application owners to refresh their key/secret pair.

• Verify the IP of the incoming request.

• Ensure applications have the least privilege access to the database.

• Encrypt connection strings in configuration files.

• Throttle or limit the rate of incoming requests to prevent denial of service attacks.

• Encrypt sensitive data, including database storage.

• Ensure the OAuth secret is hashed in the database.

• Allow only HTTPS connections.

• Set “Persist Security Info” to false in the database connection string.

• Ensure the ODS database does not accept external connections.

Recommendations for the Ed-Fi Console Bulk Loader

• Ensure Bulk Loader verifies XML content prior to parsing.

• Encrypt sensitive data.

• Encrypt connection strings in configuration files.

Recommendations for the Ed-Fi Sandbox Administration Portal

• Do not deploy the Sandbox Administration Portal to a Production instance.

• Ensure any Sandbox development tools and configurations are not included in Production.

• Remove the Swagger documentation pages from Production instances.

Security Configuration Tool

• Encrypt sensitive data.

• Ensure the OAuth secret is hashed in the database.

• Only allow HTTPS.

• Ensure that only intended system components can interact with the SMTP Send service.

• Configuration should explicitly only allow administrator access.

Key Retrieval Tool

• Ensure the secret is hashed in the database.

• Only allow HTTPS.

• Provide client application owners with guidelines for safeguarding for OAuth secrets.

• Develop protocols for compromised OAuth secrets.

Reference Models for Production Deployment

The following sections provide a number of archetypical deployment models. These reference models are not intended to be a complete prescription for any given installation, but rather a starting point to weigh options and plan a deployment that serves your organization’s needs.

On-Premises, Two-Server Deployment Model

Very small deployments (up to about 7500 students) can function on a simple, two-server model. One server hosts the API application and the Bulk Load process, and the other hosts the SQL Server platform and the ODS data store.

This configuration is excellent for small organizations because it is inexpensive, easy to maintain, and leverages common technologies that are usually supportable by in-house staff. It allows the database server to remain in the internal network while the web server is placed in the DMZ. When properly configured, this approach ensures that even in the event that a server in the DMZ is compromised, that the student data would remain secure. This model may also be used for a cloud-based or hybrid deployment.

Load-Balanced Deployment Model

A load-balanced deployment, whether on-site or in the cloud includes an HTTP Load Balancer which analyzes and routes incoming network traffic, multiple web servers, an external cache, and mirrored database servers. In this example, a basic load balancing scenario is described; more extreme examples of fault tolerance such as geographic redundancy are beyond the scope of this document.

The load balancer does exactly what its name implies, by routing incoming requests as efficiently as possible to the individual web servers, providing additional capacity as well as redundancy.

Mirrored database servers do not provide any performance or scalability improvements, but they do provide redundancy.

Multiple web servers with identical configurations are deployed and registered with the load balancer. Database configurations and connection strings are altered to implement automatic failover (https://technet.microsoft.com/en-us/library/cc917713.aspx#ECAA). The bulk-load APIs use message queueing, specifically Microsoft Message Queue (MSMQ), to coordinate the bulk load processes. Where the bulk services or bulk API exist on separate servers, or more than one server, MSMQ uses Microsoft Active Directory to manage the message queues. Each web server and bulk load server must be part of the same domain in this configuration. 

Several entity types (including types and Ed-Fi Descriptors) are cached in the web API. It is possible for these caches to get out of sync if they are local to each web server. In a load-balanced configuration, an external cache should be used.

Azure Cloud-Based Deployment Model

Azure deployments include a redundant web server for failover, although only one is active at a time. Deploying to the backup server and then swapping the primary and backup allow for higher availability and automatic failover. Performance is limited to the capabilities of one server.

Load balancing is an optional feature that is enabled when multiple servers are configured using the Microsoft Azure management console. Azure provides a load balancer as part of their platform under a multiple-server configuration.

AWS Cloud-Based Deployment Model

Amazon Web Services provides platform-as-a-service offerings suitable for cloud deployments, but has not been targeted specifically. However, automatically deploying identical servers and load balancing among them is a valuable feature that requires additional hardware and configuration in an on-site deployment configuration.

As noted above, these deployment reference models are simply starting points for planning. The section that follows discusses several techniques that may be somewhere between useful and necessary in your production environment.

Scale and Reliability Techniques for Production Deployment

Production deployments have complex techniques to achieve particular requirements for scale, security, uptime, and so forth. This section outlines a few common technologies and their applicability in an Ed-Fi ODS / API deployment.

Load Balancers

The Ed-Fi ODS / API is built to be part of a load-balanced solution. The API does not use server state information, so multiple ODS / API physical servers may be installed as part of a cloud-based or on-premises load-balanced solution. The Ed-Fi ODS / API does cache frequently used data, so a distributed cache solution must be used in a load-balanced deployment.

Domain Controllers

As mentioned in the Load Balanced Deployment model section of this document, the non-Azure configuration of the solution uses MSMQ to reliably relay messages for bulk loading between the bulk web API and bulk services. Local message queues may be used only where there is only one server with both functions on the same machine. Otherwise, MSMQ requires a shared public queue, which requires the servers to be in a domain. In a cloud deployment with multiple servers, the servers must be part of a domain.

As members of a domain, the servers may be configured to use domain service accounts for database authentication. This is the preferred configuration over SQL authentication, as it is more secure.

Continuous Integration

An automated build and continuous integration environment is a great benefit in all but the most trivial use of the Ed-Fi ODS / API. The Ed-Fi ODS / API uses code generation techniques to deeply incorporate extensions directly into the core of the compiled code. As a result, the bulk tools, libraries, database structure, API, SDK, and other artifacts are an atomic package that may not operate properly if their components are out of sync.

The Ed-Fi ODS / API also has an extensive set of unit and integration tests. These tests can take up to an hour to run.

An automated build and deploy process minimizes the chances that an unknown dependency gets injected into the code-base unintentionally, and ensures that no step process is omitted when deploying.

CPU, Memory, and SSD RAID Drives

The Ed-Fi ODS / API is a CPU- and memory-intensive solution, especially when performing bulk load operations. Using a 64-bit operating system, installing a sufficient amount of memory (recommended at least 16GB of RAM), and a server-quality CPU with several cores will maximize the performance of the web server.

Using the fastest drives available on production servers is always a good idea. With the rise of solid state disk technology in terms of improved reliability, faster data access, and improvements in capacity, it is advantageous to consider these drives over more traditional RAID spindle drives; a single SSD drive can outperform an array of spindle drives. The guiding principle of redundancy has not been repealed, however, so it is still prudent to use redundant drives for critical system components.

The Ed-Fi ODS web servers should use solid state drives where possible. Microsoft Windows and IIS perform much better when SSDs are used. From a performance perspective, it is not necessary to have a separate data drive containing the Ed-Fi ODS website. It is relatively small. The website may be easily installed in the C:\inetpub directory.

System drives should be the first drives on the database server upgraded to use solid state drives, followed by data drives. Where budget allows, the data drives may also be upgraded for a smaller (relative) performance improvement.

Database Partitioning

Databases may typically be partitioned either vertically or horizontally. In a vertical partition, different domains of data are stored on separate databases, in horizontal partitioning, different entity groups are stored on identical schema.

The Ed-Fi ODS / API vertically partitions its data from the administrative, security, and other concerns.

The ODS database has several horizontal partitioning strategies. The shared instance configuration does not partition the data. The sandbox configuration partitions data for each incoming client application based on the key and secret provided. The year-specific configuration partitions the data by year using the year in the URL.

Other partitioning strategies may be created. One custom strategy currently used by a state is to partition data by school district.

The partitioning strategy may be changed by changing the startup configuration using the owin:appStartup application setting in the Ed-Fi.Ods.Web API Web.config file.

Environmental Considerations

Every production deployment has its own environmental considerations that are unique. The following items, while not unique to the Ed-Fi ODS / API, should be considered when planning for a production deployment.

Windows Domain and Service Accounts

In any non-trivial deployment (more than a few servers), it is recommended that the IIS Servers be members of a DMZ domain. One of the key benefits of having a DMZ domain is that domain service accounts can be used for all credentials between services in the domain. Windows Authentication is more secure, and less brittle than storing usernames and passwords using clear text or encrypted configuration files.  

IIS Load Balancing

Multiple IIS servers are needed for load balancing and horizontal scaling. Provisioning multiple servers should be performed in conjunction with automated deployment scripts to minimize the potential for differences in configuration.

SMTP Relay

The administration and security tools require a SMTP service or relay to push important communications to users. The appropriate web.config file is used to configure the SMTP settings (using the mailSettings configuration section). It is highly recommended that the deliverymethod be set to PickupDirectoryFromIis, and that the IIS web servers be configured with the SMTP Relay role. Running the SMTP Relay service using a service account that are trusted by the actual SMTP server is a good way to secure the required credentials.

Microsoft Message Queue (MSMQ)

MSMQ is used to manage asynchronous messaging for the bulk API of the Ed-Fi-ODS API. In a production deployment, where there is more than one IIS server or the bulk worker service machines, message queues are stored and accessed using Active Directory. Therefore, MSMQ requires that each of these servers be joined to a domain.

Microsoft SQL Server

It is highly recommended that Windows Authentication be used instead of SQL authentication, and that SQL Server authentication be disabled in SQL Server. Running each IIS application domain as a windows service account, and providing the appropriate permissions to those service accounts in SQL server allows the connection strings to contain no user names and passwords. It is recommended that SQL Servers be mirrored and that connection strings settings include failover settings. Best practice always includes good database backup policies.

Pre-Deployment Development Tasks

The ODS / API is designed to be customized. That being the case, the as-shipped configuration of the Ed-Fi ODS is suitable for a developer machine and sandbox deployment, not a production deployment. For example, the solution ships with developer-friendly implementations that demonstrate basic functionality but may not represent functionality required for a specific installation.

Also, the Ed-Fi ODS / API is built on the Ed-Fi Data Standard, which is made to be extended. Schema extensions often include individual attributes as well as the addition of completely new entities that may be created to provide solution-specific information. A common scenario includes state education agency platform hosts that extend the data model to include information related to mandatory data collections.

Configuration considerations that your organization should evaluate include:

• An approach to Unique IDs

• Client key / secret generation and distribution scenarios

• Use of database-per-year ODS databases

• Use of per-district ODS databases

These items represent the key areas where the as-shipped components of the ODS / API must be configured for production use. A discussion of each consideration follows.

Unique Identity Systems

Because the concept of person identity is closely related to student data, the Ed-Fi ODS / API includes a common interface for accessing an Identity System. This API provides a common minimalistic interface that may be backed by an identity system of choice. Where tighter integration with an Unique Identity System is desired (such as validating identity information during data updates), the POST/PUT pipeline should be extended to call the identity system.

Client Key / Secret Distribution

Key and secret pairs are used as authorization credentials for Ed-Fi ODS / API client applications. The sandbox and security applications provide examples of how to create and distribute this sensitive information. Secure generation and distribution of these keys and secrets should receive proper attention when planning a deployment of the Ed-Fi ODS / API.

Per-Year Databases

The as-shipped configuration of the Ed-Fi ODS database does not support multi-year data sets. If platform hosts must be live during school-year transition periods, this can present operational challenges. Platform hosts may need to adapt or extend the Ed-Fi ODS / API to accommodate this requirement. A year-specific database partitioning strategy provides an approach to handling this issue, for example, but would require development and testing prior to initial deployment.

Per-District Databases

While not currently available in the Ed-Fi ODS core code base, at least one state education agency has implemented a customized per-district partitioning strategy. This approach ensures that district data is physically separated from other districts. For policy or database size reasons, this approach may be desirable.

For More Information

The information in this section is important background, but fairly general. Additional details and technical specifics are available in the GitHub repository. A few good references include:

• Configuring Higher Promotion Environments. This markdown file contains technical instructions for configuring staging environments and production servers, encrypting sensitive configuration sections, and so forth.
• How to Deploy. This markdown file contains a checklist-like view of key deployment steps along with helpful SQL scripts to perform tasks like clearing out test sandbox accounts.

The above documents are in the Ed-Fi ODS / API source code repository and so you need to be logged in to GitHub to view (though you will be provided with an amusing 404 message if you aren't logged in). See this article for more information on getting access to the source code repository.

Conclusion

Every organization has its own requirements and resources so no two deployments will be exactly alike. This document has outlined several technical options, but when evaluating your options, you should, of course, remember to take into account factors like cost, support expertise in your organization, security and privacy requirements, and so on.

For more information about the Ed-Fi ODS / API solution, visit techdocs.ed-fi.org. While the Ed-Fi Alliance doesn’t provide implementation services, it can connect organizations with vendors experienced in Ed-Fi technology deployments. Contact info@ed-fi.org for details.