If these app instances sit idle for a while, they might just be timing out their sockets. You can tweak socket settings on the driver as described here: https://github.com/datastax/java-driver/tree/3.x/manual/socket_options
Perhaps start with explicitly setting keepAlive to true as that may or may not be set depending on whether it's using the native epoll extension or NIO directly (more details about such on the page above). On Thu, Aug 31, 2017 at 3:10 AM, Ivan Iliev <ivan.iliev.il...@gmail.com> wrote: > Hello everyone, > > We are using Cassandra 3.9 for storing quite a lot of data produced from > our tester machines. > > Occasionally, we are seeing issues with apps not being able to communicate > with Cassandra nodes, returning the following errors (captured in > servicemix logs): > >> by: com.datastax.driver.core.exceptions.NoHostAvailableException: All >> host(s) tried for query failed (no host was tried) >> at com.datastax.driver.core.RequestHandler.reportNoMoreHosts( >> RequestHandler.java:218) >> at com.datastax.driver.core.RequestHandler.access$1000( >> RequestHandler.java:43) >> at com.datastax.driver.core.RequestHandler$SpeculativeExecution. >> sendRequest(RequestHandler.java:284) >> at com.datastax.driver.core.RequestHandler.startNewExecution( >> RequestHandler.java:115) >> at com.datastax.driver.core.RequestHandler.sendRequest( >> RequestHandler.java:91) >> at com.datastax.driver.core.SessionManager.executeAsync( >> SessionManager.java:132) >> ... 107 more > > > As a result, apps that try to send data to cassandra get crashed due to > running out of memory and we have to restart the containers in which they > run. > > So far I have not been able to identify what might be the cause for this > as nothing (at least I could not find anything relevant on the timestamps) > in the cassandra debug and system logs. > > Could you share some insight on this ? What to check and where to start > from , in order to troubleshoot this. > > Thanks ! > Ivan > -- ----------------- Nate McCall Wellington, NZ @zznate CTO Apache Cassandra Consulting http://www.thelastpickle.com
