I recently installed a 5 node Datastax Enterprise/Cassandra 2.1 cluster on Ubuntu 14.04 using a Datastax AMI. I was able to bring the cluster up successfully, however when I did, I received errors on console about some linux limits, shown below:
The linux limit 'memlock' is '64'. The recommended is 'unlimited'. Check your limits.conf. The linux limit 'nofile' is '4096'. The recommended is '100000'. Check your limits.conf. Check our documentation for more details. http://docs.datastax.com/en/cassandra/2.1/cassandra/install/installRecommendSettings.html?scroll=reference_ds_sxl_gf3_2k__user-resource-limits
When I checked the limits file, the memlock and nofile limits are set properly for both the cassandra and root user. However the settings are getting ignored. Has anyone else experienced this problem? I'm not that experienced with linux settings and I'm not sure where to look for an error. Sorry if this has already been asked and answered, I didn't find this question when searching.
Bob Glassett
You may want to try and reboot the systems. The package installer will try to use sysctl to set the various options at runtime, but maybe there was an issue with that.