Resolved incident
Intermittent 5xx errors
imgix · Minor · Started
- Duration
- 1h 15m
- Severity
- Minor
- Status
- Postmortem
Summary
Minor · Postmortem
# What happened On May 1st, 2023, between the hours of 08:23 UTC and 15:08 UTC, imgix experienced intermittent errors affecting a small percentage of non-cached renders. # How were customers impacted? During the affected period, a small percentage of requests to the Rendering API returned a `502` or `503` error for non-cached requests. Errors slowly and gradually increased, with <.5% of requests returning an error at the height of the incident. # What went wrong during the incident? Our upstream provider experienced communication issues between CDN POPs, causing intermittent `502`/`503` responses in a small percentage of requests to our Rendering API. The increase in errors was so minor that it did not meet our monitoring thresholds for triggering alerts. One of our engineers observed a slow increase in errors and alerted other team members to a potential issue with our service. After tracing the issue to our upstream provider, we pushed a patch to mitigate intermittent connectivity issues, resolving the incident. # What will imgix do to prevent this in the future? We have refined our alerting to better catch the slowly increasing error rates. We have also ensured that the root cause of this incident has been fixed by our upstream provider. We are also updating our traffic routing in the case that the upstream issue occurs again.
Event timeline
How this incident unfolded, from the official status page.
Postmortem
imgix
# What happened On May 1st, 2023, between the hours of 08:23 UTC and 15:08 UTC, imgix experienced intermittent errors affecting a small percentage of non-cached renders. # How were customers impacted? During the affected period, a small percentage of requests to the Rendering API returned a `502` or `503` error for non-cached requests. Errors slowly and gradually increased, with <.5% of requests returning an error at the height of the incident. # What went wrong during the incident? Our upstream provider experienced communication issues between CDN POPs, causing intermittent `502`/`503` responses in a small percentage of requests to our Rendering API. The increase in errors was so minor that it did not meet our monitoring thresholds for triggering alerts. One of our engineers observed a slow increase in errors and alerted other team members to a potential issue with our service. After tracing the issue to our upstream provider, we pushed a patch to mitigate intermittent connectivity issues, resolving the incident. # What will imgix do to prevent this in the future? We have refined our alerting to better catch the slowly increasing error rates. We have also ensured that the root cause of this incident has been fixed by our upstream provider. We are also updating our traffic routing in the case that the upstream issue occurs again.
Resolved
imgix
This incident has been resolved.
Monitoring
imgix
A fix has been implemented, and we are monitoring the results.
Identified
imgix
The issue has been identified, and a fix is being implemented.
Investigating
imgix
We are currently investigating reports of intermittent 5xx errors causing some images to initially return a 5xx error.