# Postman: ServerLess testing **URL:** \ **Category:** HiveMQ Cloud\ **Created:** [February 20, 2024, 9:11am UTC](https://community.hivemq.com/t/postman-serverless-testing/2723 "2024-02-20T09:11:41Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![lonejack](https://avatars.discourse-cdn.com/v4/letter/l/ea5d25/32.png) [@lonejack](https://community.hivemq.com/u/lonejack)\ **Post date:** [February 20, 2024, 9:11am UTC](https://community.hivemq.com/t/postman-serverless-testing/2723/1 "2024-02-20T09:11:41Z")
Hi, I’m trying to connect POSTMAN to a ServerLess account. Is there any guide? Thank you, C. ---
**Author:** ![Daria\_H](https://avatars.discourse-cdn.com/v4/letter/d/dfb087/32.png) [@Daria\_H](https://community.hivemq.com/u/Daria_H)\ **Post date:** [February 20, 2024, 10:30am UTC](https://community.hivemq.com/t/postman-serverless-testing/2723/2 "2024-02-20T10:30:33Z")
Hi @lonejack, Thank you for reaching out. Regarding your inquiry, please note that the REST API feature is not supported in HiveMQ Cloud Serverless brokers. However, this functionality is available in the Starter, Professional, and Enterprise plans. For a detailed breakdown of features associated with each plan, kindly refer to the [“Compare Features” page](https://www.hivemq.com/pricing/#:~:text=%2D%20Advanced%20observability-,Broker%20REST%20API,-Additional%20users). If you have any further questions or require additional clarification, feel free to ask. Best regards, Dasha from HiveMQ Team ---
**Author:** ![lonejack](https://avatars.discourse-cdn.com/v4/letter/l/ea5d25/32.png) [@lonejack](https://community.hivemq.com/u/lonejack)\ **Post date:** [February 20, 2024, 3:41pm UTC](https://community.hivemq.com/t/postman-serverless-testing/2723/3 "2024-02-20T15:41:46Z")
Hi @Daria_H, today I published a message to the cloud server created. Here **f4da62c516534ac98c18588f0646abdb.s1.eu.hivemq.cloud** to be precise. The result has been obtained by your mqtt utility: mqtt pub -h f4da62c516534ac98c18588f0646abdb.s1.eu.hivemq.cloud -p 8883 -s -u [USER] -pw [PASSWORD] -t ‘prova/topic’ -m ‘Ciao’ My new question is to reach the same result by my library that should use the TSL. I’m using mongoose.ws. Looking in this community (**[Need certificate to achieve SSL connexion](https://community.hivemq.com/t/need-certificate-to-achieve-ssl-connexion/1387)**) is seems that the sole certificate necessary is the isrgrootx1.pem and the feature **TLS-extension SNI**. ---
**Author:** ![lonejack](https://avatars.discourse-cdn.com/v4/letter/l/ea5d25/32.png) [@lonejack](https://community.hivemq.com/u/lonejack)\ **Post date:** [February 21, 2024, 6:33am UTC](https://community.hivemq.com/t/postman-serverless-testing/2723/4 "2024-02-21T06:33:31Z")
Hi @Daria_H , I resolved the connection from my device. So I send and receive “topics” DEVICE\<-\> **f4da62c516534ac98c18588f0646abdb.s1.eu.hivemq.cloud**. Now, might I say that my environment can communicate with a real cloud server? I see that the cloud plans the **Starter** version apply “Client certificate authentication”… Thank you, Claudio ---
**Author:** ![Daria\_H](https://avatars.discourse-cdn.com/v4/letter/d/dfb087/32.png) [@Daria\_H](https://community.hivemq.com/u/Daria_H)\ **Post date:** [February 23, 2024, 4:05pm UTC](https://community.hivemq.com/t/postman-serverless-testing/2723/5 "2024-02-23T16:05:53Z")
Hello @lonejack, Thank you for reaching out! I appreciate your interest in HiveMQ Cloud Starter. Regarding client authentication, it’s important to note that the cluster supports three distinct methods, but only one can be utilized at a time. For instance, if you’ve configured authentication using a username and password, it excludes the possibility of authenticating with certificates or JWT. Similarly, if certificate-based authentication is in place, using simpleauth or JWT is not feasible. To verify that your client is effectively communicating with the broker, you can perform actions such as connecting to the broker, subscribing to a topic, publishing, and receiving messages from that topic. Successfully executing these operations would confirm the correct interaction between the client and the broker. If you have any further questions or need additional assistance, please feel free to ask. We’re here to help! Best regards, Dasha from HiveMQ Team