Cloud Vendor Deep-Dive: PostgreSQL on DigitalOcean

DigitalOcean is a cloud service provider, more of an IaaS (Infrastructure-as-a-Service) provider which is more suitable for small to medium scale businesses. You can get to know more about DigitalOcean here. What it does is a bit different to other cloud vendors like AWS or Azure and is not heavily global yet, take a look at this video which compares DigitalOcean with AWS. 

They provide a geographically distributed computing platform in the form of virtual machines where-in businesses can deploy their applications on cloud infrastructure in an easy, fast and flexible manner. Their core focus is to provide cloud environments which are highly flexible, easy-to-set-up and can scale for various types of workloads. 

What attracted me in DigitalOcean is the “droplets” service. Droplets are Linux based VMs which can be created as a standalone or can be part of a large cloud infrastructure with a chosen Linux flavoured operating systems like CentOS, Ubuntu, etc. 

PostgreSQL on DigitalOcean

With DigitalOcean, building PostgreSQL environments can be done in two ways, one way is to build manually from scratch using droplets (only Linux based VMs) or the other way is to use managed services.

DigitalOcean started managed services for PostgreSQL with an intention to speed up the provisioning of database servers in the form of VMs on a large cloud infrastructure. Otherwise, the only way is to build PostgreSQL environments is manually by using droplets. The supported capabilities with managed services are high-availability, automatic failover, logging, and monitoring. Alerting capability does not exist yet. 

The managed services more-or-less are similar to AWS RDS. The PostgreSQL instances can be only accessed using UI, there is no access to host running the database instance. Managing, Monitoring, parameter configuration, everything must be done from a UI.

PostgreSQL Compatibility with DigitalOcean

You can build PostgreSQL environments on Digital Ocean with the droplets or go for managed services (similar to AWS RDS) which can really save your time. The only supported versions on managed services are 10 and 11. This means, businesses willing to leverage DigitalOcean’s PostgreSQL managed services will need to use/upgrade-to either version 10 or 11. Also, note that there is no support for Windows operating system. 

This blog will focus on managed services.

Managed PostgreSQL Services

DigitalOcean started providing managed PostgreSQL database services since February 2019. The intention was to introduce a faster way to provisioning infrastructure with PostgreSQL instances which can save valuable time for infrastructure database professionals. Provisioning a PostgreSQL instance is rather simple.

This can be done by logging to the DO account → go to a create database cluster page → choose the PostgreSQL version → choose the specs based on pricing → choose the location → click create. You are all good. Watch this video here for a better understanding.

High Availability

High Availability is one of the critical requirements for databases to ensure business continuity. It is imperative to ensure that high-availability meets the SLAs defined for RTO and RPO. DigitalOcean provides high-availability services in a faster and reliable manner.

Pricing

The pricing model in DigitalOcean is not complex. The price of the instance is directly proportional to the capacity and architecture of the instance. Below is an example of pricing for a standalone instance –

The capacity and pricing which suites the requirement can be chosen from the available options. Minimum is $15 per month for 10GB of disk and 1vCPU. If high-availability is a requirement, standby node can be configured as well. The limitation is that, a standby node can be added only if the primary database size is of minimum 25 GB. And, only a maximum of 5 standby nodes can be added. Below are the standby options available

If you can observe above, standby pricing is pretty simple and does not depend on the capacity. Adding one standby node will cost $20 irrespective of any size.

Access

PostgreSQL instances build using managed services can be accessed using GUIs and remotely via CLI in SSL mode only. However, PostgreSQL instances manually installed on droplets can be accessed via ssh.

Data Centres

DigitalOcean is not heavily global yet. The data centres are located in a few countries as shown below. Which means, it is not possible to deploy/run services for businesses running their services in countries other than the ones shown below.

Advantages of PostgreSQL Managed Services

Managed services for PostgreSQL is advantageous for various reasons. In my experience as a DBA, the requirement often arises to build environments for developers in a faster manner possible to perform functional, regression, and performance testing for releases. Generally, the approach would be to use tools like chef or puppet to build automation modules for applications and database environments and then use those templates to build cloud VMs. DigitalOcean’s managed services can be a great, efficient, and cost-effective option for such requirements as it is bound to be time saving. Let us take a look at the advantageous in detail –

• Opting for managed services can save a lot of time for DBAs and Developers in building PostgreSQL environments from scratch. This means, there is no database administration and maintenance overhead.
• PostgreSQL environments can be equipped with High-availability with automatic failover capability. 
• Managed instances are designed to sustain disaster. Daily backups can be configured with the PITR (point-in-time-recovery) capability. Importantly, backups are free.
• Managed PostgreSQL instances are designed to be highly scalable. DigitalOcean’s customers were able to achieve higher scalability with PostgreSQL instances and TimescaleDB extensions.
• Dashboard can be configured to monitor log files and query performance.
• Cost model of DigitalOcean is pretty simple.
• As it is a cloud infrastructure, vertical scaling can be seamless.
• Managed database instances are highly secured and optimized. A big part of the data retrieval is only possible via SSL based connections.
• Documentation is available in good detail.

Limitations of Running PostgreSQL on DigitalOcean

• PostgreSQL versions 10 and 11 are supported, no other versions can be used.
• Data centres of DigitalOcean are only available at limited geographical locations.
• The number of standby nodes cannot exceed 5.
• PITR cannot go beyond 7 days.
• Not all extensions for PostgreSQL are supported, only selected extensions can be used.
• The instances can only be up-sized. They cannot be downsized.
• Superuser access is not allowed.
• Alerting on certain thresholds is not available yet.
• Managed database instances can only be restored to a new node when restoring from backups.

Conclusion

Managed PostgreSQL services offered by DigitalOcean is a great option for businesses looking for devops type solutions for PostgreSQL environments which can really help reduce time, planning, administration, and maintenance overhead involved in building high-scale and secured PostgreSQL environments for various workloads. Their pricing model is very simple and it can be a cost-effective option. It cannot, however, really be compared to the massive cloud service providers like AWS or Azure. DigitalOcean can surely benefit businesses with its innovative cloud solutions.