I've set up below values in /etc/security/limits.conf in my RHEL machine.
* hard nofile 65535 @student hard nofile 100000 Is this the correct approach when setting a user specific max number of open files?
Should the * hard nofile value be always greater than the sum of user specific nofile values?
Should the * hard nofile value be always greater than the sum of user specific nofile values?
It does not need to be. The limits.conf(5) and limits(2) are also used for allowing some users to use more resource than default users.
Your limit entry will limits for default user(*) to open 65535 files, and for a user in the group student to open 100000.
