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Allow Invalid TLS Certificates

In development or testing scenarios, you may need to connect to an MQTT broker with a self-signed or invalid TLS certificate. This guide shows how to bypass certificate validation.

Security Warning

Disabling certificate validation exposes your application to man-in-the-middle attacks. Only use this in controlled development environments, never in production.

Example​

var options = new HiveMQClientOptionsBuilder()
    .WithBroker("broker-with-invalid-tls-cert.localhost.dev")
    .WithPort(8883)
    .WithUseTls(true)
    .WithAllowInvalidBrokerCertificates(true)
    .Build();

var client = new HiveMQClient(options);
var connectResult = await client.ConnectAsync().ConfigureAwait(false);

The WithAllowInvalidBrokerCertificates(true) call disables certificate validation, allowing connections to brokers with self-signed or expired certificates.

See Also​