Fix "Too many open files" Java IO exception – Lucidworks

Issue

Getting java.io.IOException: Too many open files in Apache Solr.

Apache Solr (all versions, Linux-based systems)

Increase the OS file descriptor limits and ensure they are applied to the Solr process. Perform the following steps to fix this issue:

Step 1. Step 1: Increase system-wide file descriptor limit

Edit /etc/sysctl.conf:

fs.file-max = 9999999 (to a high integer number if its set to low value)

To update the value do sysctl -p to apply the changes and then sysctl -a | grep file-max to verify

Step 2. Increase per-user limits. To change the ulimit setting, edit the file /etc/security/limits.conf and set the hard and soft limits.

soft   nofile         65535
hard  nofile         65535

Step 3. Reboot

Run the following commands in terminal to verify values are changed accordingly:

#cat /proc/sys/fs/file-max

9999999

#sysctl -a | grep fs.file-max

fs.file-max = 9999999

65535