The root EBS volume on the FileMage gateway was provisioned at 8 GB and ran out of space. Once full, the server could no longer write session data and began returning HTTP 500 on the portal, and remote shell access to the host was also lost.
The condition was not caught by monitoring.
Third-party services and internal Flxpoint services were unable to read or write files from the FTP service during the outage window.
All existing files at rest on the FTP server were not affected nor corrupted.
The root volume has been increased from 8 GB to 50 GB. Disk and inode usage monitors now alerts at 80% utilisation, well ahead of any failure.