Pass vault server options to plugin SDK

This is about vault plugin development SDK. When launching a vault server, I could set up the log-level option. How could I catch this value in SDK?

Specifically, I am using

BackendFactoryFunc: func(ctx context.Context, c *logical.BackendConfig) (logical.Backend, error) {
return myFactory(ctx, c, …)
TLSProviderFunc: tlsProviderFunc,

to start the server, and want to have a consistent log level in both the server and the plugin.