Merge pull request #232 from NHSDigital/cert-expiry-mgmt

Prefer auto-renew certs where appropriate

Author: iw-ezequiel

patterns/outsource-bottom-up.md

@@ -25,6 +25,8 @@ Use managed services where available and appropriate. The aim is to reduce opera
   * TO DO: close discussion about whether containers are still preferable in some use-cases
 * For data persistence prefer (where there are no other differentiating factors) pay per request options (e.g. Amazon DynamoDB, S3) to pay per time choices (e.g. Amazon Aurora or RDS).
 * In general, prefer solutions which do not involve managing VMs if possible, and ideally where there is no explicit configuration of a network (e.g. subnets, internet gateways, NAT gateways) — compare AWS Lambda which needs no network with AWS Fargate which does.
+* Where possible, outsource the management (including renewal) of certificates (e.g. via [AWS Certificate Manager](https://aws.amazon.com/certificate-manager/))
+  * Where that isn't possible, still prefer outsourcing the management of alerting for certificate expiry (see [observability](../practices/observability.md))
 
 ## Cloud native vs cloud agnostic
 

practices/observability.md

@@ -38,6 +38,7 @@
   * Tracing can be implemented using cloud platform-native tools like [AWS X-Ray](https://aws.amazon.com/xray/) or open source equivalents such as [OpenTracing](https://opentracing.io/docs/overview/what-is-tracing/). APM tools mentioned elsewhere also typically include tracing functionality.
 * More **things to monitor**.
   * Monitor (and generate alerts for) the expiry dates of the SSL certificates within the service. See [acm-cert-monitor](../tools/acm-cert-monitor/) for an example lambda and Terraform stack to monitor your AWS ACM certificates.
+    * Or, even better, outsource certificate management completely (see [outsource from the bottom up](../patterns/outsource-bottom-up.md))
   * Subscribe to service alerts from your cloud vendors, e.g. the service-status RSS feeds for [AWS](https://status.aws.amazon.com) and [Azure](https://status.azure.com/status/).
   * Ensure you have reporting and alerting for the health of any services/components your service relies on, e.g. shared network connections or shared authentication services.
 * **Secret / sensitive data**.