Introduction:

Kubernetes (K8S) is an open-source platform designed to automate deploying, scaling, and operating containerized applications. One common scenario in Kubernetes is installing and managing services like Tomcat8. However, sometimes errors can occur during the installation process, such as 'failed installing 'tomcat8' service'. In this article, I will guide you through the process of troubleshooting and resolving this issue.

Steps to troubleshoot 'failed installing 'tomcat8' service':

| Step | Description |
| ---- | ----------- |
| 1. | Check the pod status |
| 2. | Check the events for the pod |
| 3. | Check the logs of the pod |
| 4. | Check the service configuration |
| 5. | Check the networking configuration |

Step 1: Check the pod status
- Use the following command to get the status of the pod:
```bash
kubectl get pods
```

Step 2: Check the events for the pod
- Use the following command to view events related to the pod:
```bash
kubectl describe pod
```

Step 3: Check the logs of the pod
- Use the following command to view the logs of the pod to identify any error messages:
```bash
kubectl logs
```

Step 4: Check the service configuration
- Verify the service configuration to ensure it is correctly set up:
```yaml
apiVersion: v1
kind: Service
metadata:
name: tomcat8
spec:
selector:
app: tomcat8
ports:
- protocol: TCP
port: 8080
targetPort: 8080
```

Step 5: Check the networking configuration
- Ensure that the networking is properly configured to allow traffic to reach the pod:
```yaml
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: allow-tomcat8
spec:
podSelector:
matchLabels:
app: tomcat8
policyTypes:
- Ingress
- Egress
ingress: []
egress:
- to:
- ipBlock:
cidr: 0.0.0.0/0
except:
- 192.168.1.0/24
```

By following these steps and verifying each aspect of the deployment and configuration, you can troubleshoot and resolve the issue of 'failed installing 'tomcat8' service'. Remember to carefully analyze any error messages and logs to identify the root cause of the problem and make the necessary adjustments to ensure successful installation.