SElinux: How to change to permissive mode without a reboot?

I need to change selinux to "permissive mode" on a production server without a reboot, but setenforce wont let me do it(as a root), it always prints "setenforce: SELinux is disabled" What i'm doing wrong?

[root@server3 ~]# setenforce 0
setenforce: SELinux is disabled
[root@server3 ~]# setenforce 1
setenforce: SELinux is disabled
[root@server3 ~]# setenforce Permissive
setenforce: SELinux is disabled
[root@server3 ~]# getenforce
Disabled

Solution 1:

setenforce can only be used to change the mode SELinux is running in. It cannot be used to enable SELinux.

Solution 2:

So, SELinux must first be enabled as follow:

sudo nano /etc/selinux/config

then change

SELINUX=disabled

into

SELINUX=permissive

and reboot.

After reboot, you should have

# getenforce
Permissive

Solution 3:

setenforce 0 (Does not require reboot) and then check sestatus