Network Path Analyzer

Where Network Visualizer focuses on what exists, where it resides, and how gateways and subnets are linked at the infrastructure layer, Network Path Analyzer is a simulation tool that tests whether a packet with a specific source IP, destination IP, protocol, and port can successfully pass through security lists, NSGs, route tables, and firewalls. Its primary use cases include silent drop troubleshooting, pre-deployment verification, and security and compliance inspection.

Navigation

Navigation menu > Networking > Network Command Center > Network Visualizer

• Set up Network Path Analyzer policies

• Click Set up Network Path Analyzer policies

• Click Close when process shows 100% done

• If you are unable to access Network path analyzer, please contact your tenancy-admin for configuration of user policy.

• When you are all set to go click Create path analysis

Local Computer to Bastion Server

• Configure Analysis

• Source

• Destination and Direction (typically Bi-directional when we are using TCP 3-way handshake)

• Click Run analysis

• It shows unreachable lets check why

• We need to check ingress SL for public subnet of hub vcn

• We can see that the source IP is wrong lets update SL with local computer's IP address

• Analyze again

Bastion Server to Application Server

• Configure Analysis

• Source

• Destination and Direction (typically Bi-directional when we are using TCP 3-way handshake)

• Click Run analysis

• Result Reachable

Conclusion

Currently, when I was performing those tests, my instances were stopped, but they still showed as reachable because the tool only simulates the operation and checks the path it does not verify whether a server is running or stopped. Therefore, while it is better to use these tools, it is also important to troubleshoot networks manually by actually attempting a connection.