After solr is successfully executed, a warning appears as shown in the figure above.
Your Max Processes Limit is currently 3884.
Solution:
1. cd /opt/solr-7.7.2/bin [solr-7.7.2.tgz directory: /opt]
2. vi solr.in.sh
SOLR_ULIMIT_CHECKS=false
3. Restart solr [./solr start -p 8983 -force]
No more errors! !