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Adds title, description, type, domain, and tags frontmatter to every doc for improved KB semantic search. The description field is prepended to every search chunk, and domain/type/tags enable filtered queries. Type values: context, guide, runbook, reference, troubleshooting Domain values match directory structure (networking, docker, etc.) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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2.1 KiB
| title | description | type | domain | tags | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Docker Quick Troubleshooting Reference | Concise quick-reference for common Docker troubleshooting commands covering container startup, build failures, performance monitoring, network debugging, and system cleanup. | troubleshooting | docker |
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Docker Troubleshooting Reference
Container Won't Start
Check logs
docker logs <container_name>
docker logs --tail 50 -f <container_name>
Common issues
- Port already in use:
docker psto find conflicting containers - Permission errors: Check file ownership and container user
- Missing environment variables: Verify with
docker exec -it <container> env - Resource limits: Check memory/CPU constraints
Debug running container
docker exec -it <container> /bin/bash
docker exec -it <container> /bin/sh # if bash not available
Build Issues
Clear build cache
docker system prune -a
docker builder prune
Build with verbose output
docker build --progress=plain --no-cache .
Common build failures
- COPY/ADD errors: Check file paths and .dockerignore
- Package installation: Update package lists first
- Network issues: Check DNS and proxy settings
Performance Issues
Container resource usage
docker stats
docker exec <container> top
docker exec <container> free -h
Image size optimization
docker images --format "table {{.Repository}}\t{{.Tag}}\t{{.Size}}"
docker history <image>
Network Debugging
List networks and connections
docker network ls
docker network inspect <network_name>
docker port <container>
Test connectivity
docker exec <container> ping <target>
docker exec <container> nslookup <hostname>
docker exec <container> netstat -tulpn
Quick Fixes
Remove all stopped containers
docker container prune
Remove unused images
docker image prune -a
Reset Docker completely
docker system prune -a --volumes