Java reports an error saying there are too many open files 

Java may not have enough open file descriptors on Linux platforms.

The DataStax Enterprise Help Center also provides troubleshooting information.

Java may not have enough open file descriptors on Linux platforms.

DataStax Enterprise generally needs more than the default (1024) amount of file descriptors. To increase the number of file descriptors, change the security limits on your nodes as described in the Recommended production settings (dev) Recommended production settings (admin) .

Another, much less likely possibility, is a file descriptor leak. Run lsof -n | grep java to check that the number of file descriptors opened by Java is reasonable and report the error if the number is greater than a few thousand.