Hive. MQ 3. 2 - User Guide. Configuration Files. Hive. MQ is configured with sensible default settings. Therefore most users will find it sufficient to use the default values to get started. All configuration files are located in the conf folder of the Hive. MQ directory. Hive. Current release 4.7.8.95. Fix #932 Make mod name tooltip format match with other mods that add it; Improve startup logging; Fix showing multiple category tabs for. For more information about security baselines, see Deploying Java Applets With Family JRE Versions in Java Plug-in for Internet Explorer. JRE Expiration Date. Dogs have loved us for thousands of years, despite humanity’s many flaws and foibles. New research suggests dogs were domesticated from wolves just once—that’s. Our film critics on blockbusters, independents and everything in between. Java stopped running unsigned applications one day. Your security settings have blocked an untrusted application from running. The documentation states that I can add.MQ uses a simple but powerful XML based configuration. There is a XML Schema Definition File (XSD) available in the conf folder. Good text editors give you autocompletion and validation for your config. XSD file. The config. Hive. MQ startup and you have to restart Hive. MQ before any changes made during runtime are coming into effect. It’s possible to change many settings at runtime with a custom plugin, though. Changing settings with the Plugin System. Table 1. MQTT Configuration Options; Java Options Affected folder-Dhivemq.home=/your/folder/here" Base folder (bin needs to be a subfolder of this folder). Fighting malware effectively today requires new approaches, strategies, and technologies. Cisco® Advanced Malware Protection (AMP) for Networks delivers network. Often static configuration files are not sufficient for every use case. Sometimes settings need to be read from a database. Hive. MQs powerful plugin system allows to implement these kind of requirements easily and exposes many services for. Hive. MQ at runtime. The plugin development guide shows in detail how to use the plugin configuration services. Using environment variables for configuration. In many cases (docker for example) you want to configure your ports, bind adresses etc. Hive. MQ runs on. Hive. MQ supports this by providing placeholders which will be replaced with the content of environment variables at the time the configuration file is read. You can use ${YOUR_ENVVAR_NAME} anywhere in the config. Set environment variable. Use the environment variable in the configuration file< ? XMLSchema- instance". Namespace. Schema. Location="hivemq- config. HIVEMQ_PORT}< /port>. For Hive. MQ this will result in< ? XMLSchema- instance". Namespace. Schema. Location="hivemq- config. Make sure that Hive. MQ is started in the same context as your environment variables are set, otherwise Hive. MQ will not be able to access them. Default Configuration. Hive. MQ comes with sensible defaults. By default it will bind to all interfaces and port 1. Hive. MQ is configured by default with the following settings: The maximum allowed client identifier length is 6. Maximum queued (in- flight) messages are set to 1. After that limit is reached, Hive. MQ will drop messages for that client. No maximum concurrent connection limit is applied (except if you have a license which is only valid for a specific amount of concurrent connections)No throttling will take place. Clients will get disconnected if they don’t send a CONNECT message in 1. TCP connection. Hive. MQ will check for updates. See the Update Check chapter for more details. Hive. MQ Default Config< ? XMLSchema- instance". Namespace. Schema. Location="hivemq- config. Example Configurations. Hive. MQ comes with many example configurations to get you started quickly. All example configurations reside in the. If you want to use one of the example configurations, copy it to the conf folder. Adding multiple listeners. By default Hive. MQ binds to port 1. MQTT port. Hive. MQ can be configured to use multiple listeners for different protocols. These listeners can be bound. The following listener types are available: Table 2. Available listener types. Listener. Descriptiontcp- listener. A listener for MQTT which uses TCPtls- tcp- listener. A listener for MQTT which uses TLSwebsocket- listener. A listener for MQTT over websocketstls- websocket- listener. A listener for MQTT over secure websockets (TLS)The following configuration shows how to use multiple MQTT TCP Listeners. Multiple Listeners< ? XMLSchema- instance". Namespace. Schema. Location="hivemq- config. Open to the outside world - ->. Only reachable for clients on the same machine - ->. The configuration of websocket listeners is discussed in the Websocket chapter and the configuration. MQTT over TLS is discussed in the SSL/TLS chapter. You can bind different listeners to different network interfaces. If you want for example to use a plain. MQTT listener only to network interfaces for internal networks and MQTT- TLS listeners to an internet reachable interface. Update Check. Hive. MQ has an automatic update check which writes to the log file when a new version is available. The update check will send anonymized data about the Hive. MQ installation. The following data is included: The Hive. MQ version. The Hive. MQ id. Information about the system (VM Information, System Architecture (e. OS Information (e. Windows, Linux))Information of installed plugins (name, version)You can always disable the automatic update check in the config. To disable the update check apply the following configuration: Disable the update check< ? XMLSchema- instance". Namespace. Schema. Location="hivemq- config. MQTT Configuration. Hive. MQ implements the MQTT 3. MQTT 3. 1. 1 specifications to 1. For parts of the specifications which leave some parts open to the broker implementor. Hive. MQ comes with sensible default values for all settings related to MQTT. Table 3. MQTT Configuration Options. Listener. Default Value. Descriptionmax- client- id- length. The maximum allowed length of a MQTT client identifier. The retry interval for re- sending MQTT messages (like Qo. S 1 and Qo. S 2 messages) to a client in case the previous messages was not acknowledged. This time unit is in secondsno- connect- packet- idle- timeout- millis. The time for Hive. MQ to wait before disconnecting a TCP connection when no CONNECT packet arrived. Maximum Client Identifier length. The MQTT specification 3. Most applications don’t need to have such long client identifiers, so it may be useful to restrict client identifier lengths to your use case. The following examples shows how to change the maximum client identifier length limit: Change the maximum client identifier length< ? XMLSchema- instance". Namespace. Schema. Location="hivemq- config. Restrict to 2. 3 bytes to strictly conform to the MQTT 3. If a client uses a client identifier with more bytes in the CONNECT message, Hive. MQ will reject the connection. Connection Refused, identifier rejected error code. MQTT 3. 1 client identifier length. MQTT 3. 1 defined an artificial length restriction to 2. Hive. MQ omits this restriction and also allows up to 6. MQTT 3. 1 client identifiers. You can of course set. Retry Interval. MQTT systems implement the Quality of Service 1 guarantees with a two- way and the Quality of Service 2 guarantees with a four way message flow. We recommend to read this blog post if you’re interested in the details how Quality of Service Flows work. The broker (as well as the client) is required to re- send a message if it never received an acknowledgement for a particular message in the quality of service flow. Hive. MQ by default does not retry to send a message. If you are dealing with very unreliable networks and very high latency on a regular basis, it may be useful to resend messages, in case an acknowledgement takes up a large amount of time. Setting a retry interval. We strongly recommend not setting a retry interval value for Qo. S 2 use cases. If you decide to do so, you have to make sure the consumers can appropriately handle the duplicate message flag. The following example shows how to set a retry interval. Change the retry interval< ? XMLSchema- instance". Namespace. Schema. Location="hivemq- config. Resend messages only once a minute- ->. Setting the retry interval too low. If you set the retry interval too low, you could add too much pressure on MQTT clients which don’t answer fast enough (because of a slow connection or not enough processing power). So make sure the timeout is high enough that your clients have time to respond, otherwise that causes unneeded backpressure and results in lower performance instead of better performance. Connection Timeouts. MQTT, as layer 7 protocol in the OSI layer model, relies on TCP and so it’s required for clients to open a TCP connection before they can send a MQTT CONNECT message. MQTT connection. The fact that MQTT operates at application layer means that just because a client initiates a TCP connection, doesn’t necessarily mean that it initiates a MQTT connection. So malicious MQTT clients could drain server resources by opening a TCP connection and never initiating a MQTT connection by sending a MQTT CONNECT message. These kind of clients can attack your MQTT broker by draining all system resources (like memory) quickly. To avoid these kind of attacks, it’s important that you disconnect clients which don’t initiate a MQTT connection as soon as possible. Hive. MQ by default waits 1. CONNECT message of a client before it closes an open TCP socket. You can tune this behaviour to your application needs. Change the idle timeout< ? XMLSchema- instance". Namespace. Schema. Location="hivemq- config. Disconnect idle clients after 1. Clients with a slow connection. If you have clients which use a network with very high latency, a few seconds might not be enough and these clients could get disconnected although they try. CONNECT message. So make sure the timeout fits your use case. Maximum Queued In- Flight Messages. The MQTT specification states that topics must be treated as Ordered Topics. Ordered topics guarantee, that each Qo. S 1 or 2 message flow for a specific topic finishes before the next Qo. S message flow starts. That means that it is guaranteed that. Qo. S 1 and 2 messages are delivered in order. Hive. MQ treats all topics which are subscribed by a specific client as Ordered Topics. This also means, that Hive. MQ will queue Qo. S 1 and 2 messages which can’t get delivered immediately to a client because another message flow for the topic is in progress. If the client consumes messages slower than new matching messages are received by Hive. MQ, these new messages will queue up for that specific client. Because this can drain system resources (memory) quickly. Hive. MQ will discard messages if the configured max- queued- messages limit is exceeded for a specific client. The queued message limit is the limit for all queued messages of an individual client, independent of the number of concrete topics the client subscribed to.
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