Application Deployment Failures - Troubleshooting Guide
Application deployment failures preventing releases? Quick steps to identify deployment issues, fix deployment problems, and restore application functionality.
Application Deployment Failures - Troubleshooting Guide
Deployment failed, application not working, release broken. This guide gives you immediate steps to diagnose and fix application deployment failures—now. No theory, just action.
For setting up monitoring to prevent this in the future, see Application Deployment and Releases Monitoring Guide after you've resolved the immediate crisis.
60-Second Triage
Run these commands in order:
# Step 1: Check deployment logs (takes 10 seconds)
tail -100 /var/log/deployment.log
# Step 2: Check application status (takes 5 seconds)
systemctl status application.service
# Step 3: View deployment errors (takes 10 seconds)
grep -i "error\|fail" /var/log/deployment.log | tail -20
# Step 4: Verify application health (takes 5 seconds)
curl -f http://localhost:8080/health || echo "Application not responding"
Common Deployment Issues and Quick Fixes
| Issue | Likely Cause | Quick Fix |
|---|---|---|
| Deployment script failed | Script errors | Check script: bash -x deployment-script.sh |
| Application won't start | Configuration errors | Check config: cat /etc/application/config.conf |
| Dependencies missing | Package not installed | Install dependencies: sudo apt install missing-package |
| Port conflict | Port already in use | Change port or stop conflicting service |
Symptoms of Deployment Failures
Deployment failures manifest in several ways:
- Deployment script errors: Scripts fail with errors
- Application won't start: Services fail to start after deployment
- Configuration errors: Applications can't read configuration
- Dependency issues: Missing or incompatible dependencies
Step-by-Step Troubleshooting
Step 1: Identify Deployment Failures
When deployments fail:
-
Check Deployment Logs:
tail -100 /var/log/deployment.log grep -i "error\|fail" /var/log/deployment.log | tail -20 -
Verify Deployment Status:
test -f /var/www/app/.deployed && echo "Deployed" || echo "Not deployed" -
Check Application Status:
systemctl status application.service
Step 2: Investigate Deployment Issues
Once you identify deployment failures:
-
Review Deployment Errors:
grep -i "error\|fail\|exception" /var/log/deployment.log | tail -50 -
Check Application Logs:
tail -100 /var/log/application.log -
Verify Application Configuration:
cat /etc/application/config.conf
Step 3: Fix Deployment Issues
When deployment issues are identified:
-
Fix Deployment Script Errors:
bash -x deployment-script.sh -
Restore Application Configuration:
cp /backup/config.conf /etc/application/config.conf systemctl restart application.service -
Rollback Deployment:
cd /var/www/app && git checkout previous-version systemctl restart application.service
Step 4: Prevent Future Deployment Failures
To prevent deployment failures:
-
Monitor Deployments Continuously:
- Use Zuzia.app to monitor deployment status
- Set up alerts for deployment failures
- Track deployment success rates
-
Test Deployments in Staging:
- Test deployments in non-production environments
- Verify applications work after deployment
- Document deployment procedures
Automatic Detection with Zuzia.app
Zuzia.app automatically monitors deployments and detects failures:
- Checks deployment status every few minutes
- Detects deployment failures immediately
- Sends alerts when deployments fail
- Tracks deployment history
Set up deployment monitoring in Zuzia.app to prevent failures:
- Add scheduled task:
test -f /var/www/app/.deployed && echo "OK" || echo "FAIL" - Configure alerts for deployment failures
- Monitor deployment continuously
Best Practices for Preventing Deployment Failures
1. Monitor Deployments Continuously
Don't wait for deployment failures:
- Use Zuzia.app for continuous deployment monitoring
- Set up alerts before deployment issues become critical
- Review deployment logs after each deployment
2. Test Deployments Before Production
Test deployments in staging:
- Verify deployments work correctly
- Test application functionality after deployment
- Document deployment testing procedures
3. Maintain Deployment Documentation
Keep deployment documentation current:
- Document all deployment procedures
- Maintain deployment change logs
- Update documentation when procedures change
FAQ: Common Questions About Deployment Failures
How do I know if deployment failed?
Check deployment logs: tail -100 /var/log/deployment.log. Check deployment status: test -f /var/www/app/.deployed. Verify application status: systemctl status application.service.
What should I do immediately when deployment fails?
Immediately check deployment logs: tail -100 /var/log/deployment.log. Review deployment errors: grep -i "error\|fail" /var/log/deployment.log. Check application status: systemctl status application.service. Rollback if necessary.
Can deployment failures cause service outages?
Yes, if deployments fail and applications don't start, services can become unavailable.
How can Zuzia.app help prevent deployment failures?
Zuzia.app monitors deployment status continuously, detects deployment failures immediately, sends alerts when deployments fail, and tracks deployment history.