NoHostAvailableException .TransportException: Error writing while connecting to cassandra (Automation) - automation

Question

For my automation project, i am trying to integrate cassandra to spring boot jpa using datastasx driver and
Caused by: com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: api-beta.caas.dbattery.akamai.com/x.x.x.x:9042 (com.datastax.driver.core.exceptions.TransportException: [api-beta.caas.dbattery.akamai.com/x.x.x.x:9042] Error writing), api-beta.caas.dbattery.akamai.com/x.x.x.x:9042 (com.datastax.driver.core.exceptions.TransportException: [api-beta.caas.dbattery.akamai.com/x.x.x.x:9042] Error writing), api-beta.caas.dbattery.akamai.com/x.x.x.x:9042 (com.datastax.driver.core.exceptions.TransportException: [api-beta.caas.dbattery.akamai.com/x.x.x.x:9042] Error writing))
In POM.xml
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.1.RELEASE</version>
<relativePath/>
</parent>
<properties>
<spring.boot.version>2.1.1.RELEASE</spring.boot.version>
<datastax.driver.version>3.10.2</datastax.driver.version>
</properties>
<dependency>
<groupId>com.datastax.cassandra</groupId>
<artifactId>cassandra-driver-core</artifactId>
<version>${datastax.driver.version}</version>
</dependency>
<dependency>
<groupId>com.datastax.cassandra</groupId>
<artifactId>cassandra-driver-mapping</artifactId>
<version>${datastax.driver.version}</version>
</dependency>
<dependency>
<groupId>com.datastax.cassandra</groupId>
<artifactId>cassandra-driver-extras</artifactId>
<version>${datastax.driver.version}</version>
</dependency>
<dependency>
<groupId>io.netty</groupId>
<artifactId>netty-tcnative</artifactId>
<version>2.0.34.Final</version>
</dependency>
<dependency>
<groupId>io.netty</groupId>
<artifactId>netty-tcnative-boringssl-static</artifactId>
<version>2.0.34.Final</version>
</dependency>
<dependency>
<groupId>io.netty</groupId>
<artifactId>netty-transport-native-epoll</artifactId>
<version>4.1.54.Final</version>
</dependency>

Answer 1

I suspect you were getting other exceptions like OperationTimedOutException when the driver attempts to connect to the nodes in the list but continually failed.
The driver generates a query plan which is a list of nodes to contact for an app query. The driver cycles through this list one node at a time until it is able to connect to all of them. After it has tried to connect to all nodes in the list (which all failed), the driver returns NoHostAvailableException: All host(s) tried for query failed.
The most common causes for this are (1) network connectivity issues, or (2) nodes being down or unresponsive. There is a good chance that the cluster nodes are listening on a different IP address that you are connecting to.
It sounds like you're trying this out for the first time and you might find it easier to just focus on coding your app by connecting to Astra so you don't have to worry about the DB side of things. There's a Spring sample app that you could look at that will get you up and running in literally a few minutes. Cheers!