PURE-FTPD in Linux "Login failed: 530 login authentication Failed"

Again encounter PURE-FTPD "Login failure: 530 login Authentication Failed" problem, this time the reason is that the virtual user UID is less than pure-ftpd.conf minuid value, now detailed description of the entire error-checking process.

In general, I use Yum to install PURE-FTPD, and directly use Puredb to verify the user's login, everything is for convenience and quick. This time also, after installation, add virtual users, bind to the directory/data/www, but this time give the virtual user specified user and group is Apache, its UID and GID is 48:

Apache:x:48:48:apache:/data/www:/sbin/nologin
Nginx:x:498:498:nginx User:/data/cache/nginx:/sbin/nologin

Log on using lftp, and prompt for error messages:

LFTP admin@192.168.1.168:~> ls
----is connecting to 192.168.1.168 (192.168.1.168) port 21
<-------------Welcome to pure-ftpd [PRIVSEP] [TLS]----------
<---220-you are user number 1 allowed.
<---220-local time are now 08:51. Server port:21.
<---220-this is a private system-no anonymous login
<---You are disconnected after minutes of inactivity.
---> FEAT
<---211-extensions supported:
<---EPRT
<---IDLE
<---MDTM
<---SIZE
<---REST STREAM
<---mlst type*;size*;sizd*;modify*; unix.mode*; unix.uid*; unix.gid*;unique*;
<---MLSD
<---AUTH TLS
<---Pbsz
<---Prot
<---UTF8
<---ESTA
<---PASV
<---EPSV
<---SPSV
<---ESTP
<---211 end.
---> AUTH TLS
<---The security scheme isn't not implemented
---> OPTS UTF8 on
<---OK, UTF-8 enabled
---> OPTS mlst type;size;modify; Unix.mode; Unix.uid; Unix.gid;
<---mlst OPTS type;size;sizd;modify; Unix.mode; Unix.uid; Unix.gid;unique;
---> USER admin
<---331 User admin OK. Password Required
---> Pass XXXX
<---530 Login authentication failed
---> PWD
LS: Login failed: 530 login authentication failed
<---530 you aren ' t logged in
---> QUIT
<---221-goodbye. You uploaded 0 and downloaded 0 kbytes.
<---221 Logout.
----Turn off control connections

And the error message found in the/var/log/messages:

Feb 08:46:32 test pure-ftpd: (? @192.168.1.10) [INFO] New connection from 192.168.1.10
Feb 08:46:34 test pure-ftpd: (? @192.168.1.10) [WARNING] Can ' t login as [admin]: Account Disabled
Feb 08:46:38 test pure-ftpd: (? @192.168.1.10) [INFO] Logout.
Feb 08:46:50 test pure-ftpd: (? @192.168.1.10) [INFO] New connection from 192.168.1.10
Feb 08:46:51 test pure-ftpd: (? @192.168.1.10) [WARNING] Can ' t login as [admin]: Account Disabled
Feb 08:46:53 test pure-ftpd: (? @192.168.1.10) [INFO] Logout.

have been thinking, how will appear account disabled, oneself have not done the action of disabling accounts, only a line of view pure-ftpd.conf configuration content, when the view to minuid this row, suddenly wake up, please see:

# Minimum UID for a authenticated user to log in.
Minuid 500

Everything's clear. The PURE-FTPD configuration allows only the UID greater than or equal to 500 before you can log on to FTP, so the workaround is:
1. Set the minuid of the configuration file to 48, save the reboot pure-ftpd
2. Create a new FTP user with a UID greater than 500, reassign the virtual user uid and GID