Non-technical Description

SSL certificates are used by websites to ensure that communication to/from the website is secure, each certificate is valid for a certain length of time.

The certificates used for TIS were due to expire on the 15th April and were replaced on the 6th April.

While making some unrelated changes the outdated certificates were accidentally deployed back to TIS.

Trigger

• api-gateway playbook ran, removing manually updated certificates

Detection

• Detected by dev team and then reported by users shortly afterwards
  

  

  
  

Resolution

• Liban Hirey (Unlicensed) managed to recover new certificates from the stage environment and copied them to the prod blue/green servers

• forgotten branch containing the new certificates was pushed and merged to github

• Prod tested and found to be working well.

Timeline

• 07 May 2021: 14:55 BST - Ansible playbook ran to apply changes to api-gateway

• 07 May 2021: 14:59 BST - Detected by dev team and users

• 07 May 2021: 14:30 BST - Fix deployed

• 10 May 2021: Discovered failures in reading files from ESR. There were 3 attempts to trigger processing the file DE_NWN_APC_20210506_00002693.DAT which all failed with an SSL Exception.

Root Cause(s)

• Ansible playbook replaced latest certificates with outdated ones

• The updated certificates were added manually, so the playbook didn’t know about them

• branch containing the new certificates and not been pushed to GitHub

Action Items

Lessons Learned

• Make sure anything applied manually will be handled automatically or do it automatically from the start