Does Limits.d file overwrites to limits.conf file ?

Does limits.d will overwrite to limits.conf file ?. Below you can see how it works ?

Below you can see ulimit values setup in limits.d file for user "john" and thier is nothing in limits.conf

[root@linuxtechnotes ~]# cat /etc/security/limits.d/90-nproc.conf
# Default limit for number of user's processes to prevent
# accidental fork bombs.
# See rhbz #432903 for reasoning.

*          soft    nproc     1024
root       soft    nproc     unlimited

john  soft nproc 8000
john  hard nproc 8000
john  soft nofile 8000
john  hard nofile 8000

[root@linuxtechnotes ~]# su - john
[john@linuxtechnotes ~]$ ulimit -n -u
open files                      (-n) 8000
max user processes              (-u) 8000
[john@linuxtechnotes ~]$ cat /etc/security/limits.conf | tail -3
#@student        -       maxlogins       4

# End of file
[john@linuxtechnotes ~]$ whoami
john

[john@linuxtechnotes ~]$ 

Now below you can see i have setup values as 65535 in limits.conf file and 8000 in limits.d file . you can see below on which file wins 


[root@linuxtechnotes ~]# cat /etc/security/limits.d/90-nproc.conf
# Default limit for number of user's processes to prevent
# accidental fork bombs.
# See rhbz #432903 for reasoning.

*          soft    nproc     1024
root       soft    nproc     unlimited

john  soft nproc 8000
john  hard nproc 8000
john  soft nofile 8000
john  hard nofile 8000

[root@linuxtechnotes ~]# su - john
[john@linuxtechnotes ~]$ ulimit -n -u
open files                      (-n) 8000
max user processes              (-u) 8000
[john@linuxtechnotes ~]$ cat /etc/security/limits.conf | tail -3
#@student        -       maxlogins       4

# End of file
[john@linuxtechnotes ~]$ whoami
john
[john@linuxtechnotes ~]$ exit
logout
[root@linuxtechnotes ~]# vi /etc/security/limits.conf
[root@linuxtechnotes ~]# cat /etc/security/limits.conf | tail -5
# End of file
john soft nofile 65535
john hard nofile 65535
john soft nproc 65535
john hard nproc 65535
[root@linuxtechnotes ~]# su - john
[john@linuxtechnotes ~]$ ulimit -n -u
open files                      (-n) 8000
max user processes              (-u) 8000
[john@linuxtechnotes ~]$ whoami
john

[john@linuxtechnotes ~]$ exit

so as you see above limits.d wins . its means limits.d over writes to limits.conf file . Now Below lets try to remove the values in limits.d file and see which values reflects .


[root@linuxtechnotes ~]# cat /etc/security/limits.conf | tail -5
# End of file
john soft nofile 65535
john hard nofile 65535
john soft nproc 65535
john hard nproc 65535
[root@linuxtechnotes ~]# su - john
[john@linuxtechnotes ~]$ ulimit -n -u
open files                      (-n) 8000
max user processes              (-u) 8000
[john@linuxtechnotes ~]$ whoami
john
[john@linuxtechnotes ~]$ exit
logout
[root@linuxtechnotes ~]# cat /etc/security/limits.d/90-nproc.conf
# Default limit for number of user's processes to prevent
# accidental fork bombs.
# See rhbz #432903 for reasoning.

*          soft    nproc     1024
root       soft    nproc     unlimited

john  soft nproc 8000
john  hard nproc 8000
john  soft nofile 8000
john  hard nofile 8000

[root@linuxtechnotes ~]# vi /etc/security/limits.d/90-nproc.conf
[root@linuxtechnotes ~]# cat /etc/security/limits.d/90-nproc.conf
# Default limit for number of user's processes to prevent
# accidental fork bombs.
# See rhbz #432903 for reasoning.

*          soft    nproc     1024
root       soft    nproc     unlimited


[root@linuxtechnotes ~]# su - john
[john@linuxtechnotes ~]$ ulimit -n -u
open files                      (-n) 65535
max user processes              (-u) 65535
[john@linuxtechnotes ~]$ whoami
john

[john@linuxtechnotes ~]$