k3s-gitops/apps/demo-nginx/docs/README.md

Demo Nginx Documentation

Документация для demo-nginx deployment с автоматическим и ручным rollback.

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📚 Available Documentation

ROLLBACK_MANUAL.md

Comprehensive Manual Rollback Guide

Полная документация по функции ручного rollback:

• 3 способа rollback (IMAGE_TAG, REVISION, GIT_COMMIT)
• Setup guide
• Troubleshooting со всеми fixes
• Best practices
• Examples
• FAQ

When to use: Нужна детальная информация или troubleshooting

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ROLLBACK_QUICK_REF.md

Quick Reference Card

Краткая справка для быстрого использования:

• Quick start (2 минуты)
• 3 способа rollback
• Emergency procedure
• Verification commands
• Checklist

When to use: Быстрый rollback в production

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🎯 Quick Links

Rollback Feature

• Full Guide: ROLLBACK_MANUAL.md
• Quick Ref: ROLLBACK_QUICK_REF.md
• Jenkinsfile: Jenkinsfile.rollback
• CI/CD Guide: ../../../CICD_GUIDE.md

Related Resources

• Jenkins RBAC: apps/jenkins/rbac.yaml
• Deployment: deployment.yaml
• Main CI/CD: Jenkinsfile

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🚀 Quick Start

Manual Rollback (2 minutes)

1. Jenkins → demo-nginx-rollback
2. IMAGE_TAG + main-21
3. SKIP_HEALTH_CHECK: true
4. Build

See ROLLBACK_QUICK_REF.md for details.

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Emergency Rollback (30 seconds)

kubectl rollout undo deployment/demo-nginx -n demo-app

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📊 Features Summary

Manual Rollback

✅ 3 rollback methods (IMAGE_TAG, REVISION, GIT_COMMIT)
✅ GitOps sync (auto-commit to Git)
✅ Zero downtime (rolling updates)
✅ DRY_RUN mode (safe testing)
✅ Full RBAC permissions
✅ Input validation (auto-trim)
✅ Retry logic (5 attempts)
⚠️ Health check optional (use SKIP_HEALTH_CHECK=true)

Automatic Rollback

✅ Triggered on deployment failure
✅ Saves previous state
✅ Kubernetes rollback
✅ Git revert
✅ Health checks
✅ Timeout protection

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🐛 All Fixes Applied

#	Issue	Fix	Status	Doc
1	Container name	Use nginx	✅	Link
2	Whitespace	Auto-trim	✅	Link
3	RBAC	pods/exec perm	✅	Link
4	Health timing	SKIP option	⚠️	Link
5	Bash loop	Explicit list	✅	Link

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💡 Recommended Reading Order

For New Users:

1. Start → ROLLBACK_QUICK_REF.md
2. Practice → Follow quick start
3. Deep Dive → ROLLBACK_MANUAL.md

For Troubleshooting:

1. Check → ROLLBACK_MANUAL.md - Troubleshooting
2. Verify → ROLLBACK_QUICK_REF.md - Verification
3. Support → ROLLBACK_MANUAL.md - Support

For Emergency:

1. Fast → ROLLBACK_QUICK_REF.md - Emergency
2. Alternative → ROLLBACK_MANUAL.md - Emergency

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🎓 Key Concepts

Rollback Methods Comparison

Method	Speed	Precision	Use Case
IMAGE_TAG	⚡⚡⚡	🎯 High	Known build number
REVISION	⚡⚡	🎯 Medium	Recent rollback
GIT_COMMIT	⚡	🎯🎯 High	Exact code state

When to Use What

Use IMAGE_TAG when:

• You know the build number (main-21)
• Quick rollback needed
• Most common scenario

Use REVISION_NUMBER when:

• Need to go back N versions
• Don't remember exact tag
• Working with kubectl history

Use GIT_COMMIT when:

• Need exact code state
• Multiple changes in one build
• Precise rollback required

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📈 Monitoring

Check Rollback Status

# Deployment status
kubectl get deployment demo-nginx -n demo-app

# Pod status
kubectl get pods -n demo-app -l app=demo-nginx

# Rollout history
kubectl rollout history deployment/demo-nginx -n demo-app

# ArgoCD status
kubectl get application demo-nginx -n argocd

Grafana Queries

# Rollback count
sum(increase(deployment_rollback_total[1h])) by (deployment)

# Rollback rate
rate(deployment_rollback_total[5m])

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❓ FAQ

Q: Какой метод rollback использовать?

A: Для большинства случаев используй IMAGE_TAG - самый быстрый и простой.

Q: Health check всегда падает, это баг?

A: Нет, это timing issue во время rolling update. Используй SKIP_HEALTH_CHECK: true и проверь вручную через минуту.

Q: Как быстро откатиться в emergency?

A: Используй kubectl rollout undo (30 секунд) или Jenkins с SKIP_HEALTH_CHECK (2 минуты).

Q: Где полная документация?

A: ROLLBACK_MANUAL.md - comprehensive guide со всеми details.

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🆘 Support

Need Help?

1. Check ROLLBACK_MANUAL.md - Troubleshooting
2. Review ROLLBACK_MANUAL.md - FAQ
3. Check Jenkins console output
4. Verify RBAC permissions
5. Review pod status and logs

Still stuck?

• Jenkins logs: Jenkins → Build → Console Output
• K8s events: kubectl get events -n demo-app
• Pod logs: kubectl logs -n demo-app -l app=demo-nginx

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📝 Documentation Updates

Last Updated: 2026-01-06
Version: 1.0
Status: Production Ready ✅

Recent Changes:

• ✅ Added comprehensive manual rollback guide
• ✅ Added quick reference card
• ✅ Documented all 5 fixes
• ✅ Added examples and best practices
• ✅ Production-ready feature

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Ready to rollback? Start with Quick Reference! 🚀