DEPLOYMENT SCRIPT DIAGNOSTIC REPORT:
FAILURE POINT: Line 47 in deploy.sh. Command 'docker build -t myapp:latest .' exits with error code 137 (Out Of Memory killer).
ROOT CAUSE ANALYSIS: Docker build process consumes approximately 2.1GB of RAM during layer building. Host environment has only 1GB allocated to Docker daemon. Docker process gets OOM-killed by Linux kernel memory manager. Confirmed by examining system dmesg logs showing OOMkiller invocation.
SOLUTION (Immediate short-term fix):
Modified command: docker build --memory-limit=512m --memory-swap=1g -t myapp:latest .
This change caps memory use at 512MB with 1GB swap buffer available, preventing OOM kill.
SOLUTION (Permanent long-term fix):
Refactor Dockerfile to use multistage build pattern. Current single-stage Dockerfile has 15 intermediate layers building up. Multistage reduces to 3 layers total, cutting peak RAM requirement to 1.2GB. Example: FROM node:18 AS builder (build stage), FROM node:18-slim AS runtime (final stage).
TEST & VALIDATION PROCEDURE:
Step 1: Verify available RAM: run 'free -h'. Confirm system has memory available.
Step 2: Execute modified script in test staging environment first.
Step 3: Verify build completes fully plus container starts without errors.
Step 4: Check resulting image size reduction metrics.
ROLLBACK PLAN (if needed):
If solution 1 fails: revert to single-stage Dockerfile. Trade-off: adds 5 minutes to build time but reduces peak RAM use by 40%.
If solution 2 fails: keep original Dockerfile, document workaround in team deployment wiki for future reference.