java.lang.AssertionError from Java Agent

[DanMan259]

I implemented the metrics collector on Cassandra 3.11 and got the following log on startup.

Running on RHEL 7, and ppc64le architecture.

INFO [main] 2021-01-18 23:19:58,353 CassandraDaemonInterceptor.java:61 - Starting DataStax Metric Collector for Apache Cassandra 0.1.13
ERROR [main] 2021-01-18 23:19:58,355 CassandraDaemon.java:774 - Exception encountered during startup
java.lang.AssertionError: null
	at com.datastax.mcac.UnixSocketClient.epollGroup(UnixSocketClient.java:235) ~[datastax-mcac-agent.jar:na]
	at com.datastax.mcac.UnixSocketClient.start(UnixSocketClient.java:289) ~[datastax-mcac-agent.jar:na]
	at com.datastax.mcac.interceptors.CassandraDaemonInterceptor.intercept(CassandraDaemonInterceptor.java:62) ~[datastax-mcac-agent.jar:na]
	at org.apache.cassandra.service.CassandraDaemon.start(CassandraDaemon.java) [apache-cassandra-3.11.6.jar:3.11.6]
	at org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:645) [apache-cassandra-3.11.6.jar:3.11.6]
	at org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:757) [apache-cassandra-3.11.6.jar:3.11.6]
INFO [StorageServiceShutdownHook] 2021-01-18 23:19:58,358 HintsService.java:209 - Paused hints dispatch
INFO [StorageServiceShutdownHook] 2021-01-18 23:19:58,362 Server.java:179 - Stop listening for CQL clients
INFO [StorageServiceShutdownHook] 2021-01-18 23:19:58,362 Gossiper.java:1647 - Announcing shutdown

[sri-postgres-cassandra]

I am facing same issue, can you please let me know if you were able to solve this issue

[jsanda]

@sri-postgres-cassandra What OS/arch are you running on?

[jdonenine]

For reference we found a similar issue in some work we were doing on the management-api where epoll wasn't available on MacOS: https://github.com/k8ssandra/management-api-for-apache-cassandra/issues/128

[sri-postgres-cassandra]

Thank You @jsanda and @jdonenine .

I am using RHEL 8 OS . I was able to fix this issue by granting exec privileges to /tmp directory .After grant exec privileges to /tmp directory metric collector on Cassandra 3.11 started.

sudo mount -o remount,exec /tmp