Comprehensive and Detailed In-Depth Explanation:
1. Understanding the Network Setup
* PC1 (192.168.1.1/24) and PC2 (192.168.1.2/24) are connected to SW1.
* Both PCs are in the same VLAN, meaning communication should work without routing.
* If there is a communication failure, it could be due to physical, VLAN, ARP, or port security issues.
2. Evaluating Each Answer Option
* Option A: "SW1's GE0/0/2 is shut down."
* Correct.
* If GE0/0/2 is shut down, PC2 cannot send or receive traffic, causing communication failure.
* Even if PC1 is working, PC2 will be unreachable.
* # A is a valid cause.
* Option B: "The link of SW1's GE0/0/1 is faulty."
* Correct.
* If GE0/0/1 has a faulty link, PC1 cannot communicate with PC2, causing failure.
* Even if PC2 is working, PC1 will be unreachable.
* # B is a valid cause.
* Option C: "Incorrect static ARP entries are configured on the hosts."
* Correct.
* If static ARP entries are incorrectly configured, PCs will map the wrong MAC addresses to IPs.
* This will result in packet delivery failures, even if the physical network is working.
* # C is a valid cause.
* Option D: "Port isolation is configured on SW1."
* Correct.
* Port isolation (or private VLAN) prevents direct communication between specific ports.
* If port isolation is enabled on GE0/0/1 and GE0/0/2, PC1 and PC2 will be unable to reach each other.
* # D is a valid cause.
Final Answer:
# A, B, C, and D are correct.
HCIP-Datacom-Advanced Routing & Switching Technology References:
* Troubleshooting VLAN and Layer 2 Communication Issues
* Impact of Port Isolation and Private VLANs on Communication
* Static ARP Entry Configuration and Its Effects on Network Connectivity