[Bug] Please Describe the Bug

[aaron-ai]

Before Creating the Bug Report

• I found a bug, not just asking a question, which should be created in GitHub Discussions.

• I have searched the GitHub Issues and GitHub Discussions of this repository and believe that this is not a duplicate.

• I have confirmed that this bug belongs to the current repository, not other repositories of RocketMQ.

Programming Language of the Client

C#

Runtime Platform Environment

K8s Linux with ipvlan enabled.

RocketMQ Version of the Client/Server

C# SDK 5.1.0

Run or Compiler Version

No response

Describe the Bug

Utilities#GetMacAddress() may return null in some situations.

Steps to Reproduce

Invoke Utilities#GetMacAddress()

What Did You Expect to See?

In any situation, a valid MAC address can be obtained.

What Did You See Instead?

a null mac address is returned.

Additional Context

No response