Configure ulimit using Pluggable Authentication Modules using the Command Line

Follow these command-line instructions to configure ulimit using Pluggable Authentication Modules on systems that do not use Cloudera Manager.

If you are using ulimit, you must make the following configuration changes:

In the /etc/security/limits.conf file, add the following lines, adjusting the values as appropriate. This assumes that your HDFS user is called hdfs and your HBase user is called hbase.
```
hdfs  -       nofile  32768
hdfs  -       nproc   2048
hbase -       nofile  32768
hbase -       nproc   2048
```
note
- Only the root user can edit this file.
- If this change does not take effect, check other configuration files in the /etc/security/limits.d/ directory for lines containing the hdfs or hbase user and the nofile value. Such entries may be overriding the entries in /etc/security/limits.conf.
To apply the changes in /etc/security/limits.conf on Ubuntu and Debian systems, add the following line in the /etc/pam.d/common-session file:
```
session required  pam_limits.so
```
For more information on the ulimit command or per-user operating system limits, refer to the documentation for your operating system.