DL3012: Multiple HEALTHCHECK instructions
Error Reliability
Why This Matters
Only the last HEALTHCHECK instruction takes effect. Multiple HEALTHCHECK instructions are always a mistake because the earlier ones are silently overridden. This causes confusion when health checks do not behave as expected because the intended check was overridden by a later one. Keep a single HEALTHCHECK per Dockerfile.
How to Fix
Remove duplicate HEALTHCHECK instructions, keep only the final one
Before (incorrect)
HEALTHCHECK CMD curl http://localhost/
HEALTHCHECK CMD curl http://localhost/healthAfter (correct)
HEALTHCHECK CMD curl http://localhost/healthRule Details
- Rule Code
- DL3012
- Severity
- Error
- Category
- Reliability