How add FTP user from backend in linux?

Use following commands :

Environment : RHEL 6, vsftpd

[root@vm91 ~]# useradd -m testing -G users,ftp,wheel -s /bin/bash
[root@vm91 ~]# passwd testing
Changing password for user testing.
New password:
BAD PASSWORD: it is based on a dictionary word
BAD PASSWORD: is too simple
Retype new password:
passwd: all authentication tokens updated successfully.
[root@vm91 ~]#

[root@vm91 ~]# ll -dr /home/*|grep testing
drwx------. 2 testing testing 4096 May 11 06:58 /home/testing
[root@vm91 ~]#

Test the settings :

You may get following error :

[kmaiti@kmaiti ~]$ ftp IP_FTP_server
Connected to FTP_server (*****).
220 (vsFTPd 2.2.2)
Name (*****:kmaiti): testing
331 Please specify the password.
Password:
500 OOPS: cannot change directory:/home/testing

---

just do like : # getsebool ftp_home_dir
then #setsebool -P ftp_home_dir on

Then retry to access the FTP server :

-----
[kmaiti@kmaiti ~]$ ftp FTP_IP
Connected to ser (ser).
220 (vsFTPd 2.2.2)
Name (ser:kmaiti): testing
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp>
-----

Try :)