Name service caching

Cloudera recommends that you enable name service caching, particularly for clusters that use non-local Hadoop functional accounts, such as the hdfs and yarn users. This becomes critical in the case where the latter is combined with using Kerberos. Many difficult-to-diagnose problems can arise when name service lookups time out or fail during heavy cluster utilization.

Enable the Name Service Cache Daemon (nscd) by running the following commands on RHEL and CentOS 7 operating systems:
systemctl start nscd.service
systemctl enable nscd.service

If you are running Red Hat SSSD, then you must modify the nscd configuration to not cache the passwd, group, or netgroup information.