CentOS: How can I see pure-ftpd server response logs?

My ftp user face error like this:

FTP 127 Response: 500 I won't open a connection to xxx.xxx.xxx.xxx (only to yyy.yyy.yyy.yyy)

This is the response of my server which captured by Wireshark in a windows ftp client.

I enabled the VerboseLog in /etc/pure-ftpd.conf and there is line which says:

#If you want to log all client commands, set this to "yes".
#This directive can be specified twice to also log server responses. 
#VerboseLog yes

So I edited my config file and brought the VerboseLog yes twice to log server response something like this:

# If you want to log all client commands, set this to "yes".
# This directive can be specified twice to also log server responses.

VerboseLog yes

VerboseLog yes

However still I cannot find logs in /var/log/message for this error anywhere.
Can somebody say what is wrong?
P.S.: I want to have logs since I want to monitor the status of server and check if problem still arise or not. I’m not looking for capturing or snooping the interfaces as a temporary solution/workaround.

Here is my /etc/pure-ftpd.conf:

############################################################
#                                                          #
#             Configuration file for pure-ftpd             #
#                                                          #
############################################################

# If you want to run Pure-FTPd with this configuration
# instead of command-line options, please run the
# following command :
#
# /usr/sbin/pure-ftpd /etc/etc/pure-ftpd.conf
#
# Online documentation:
# https://www.pureftpd.org/project/pure-ftpd/doc


# Restrict users to their home directory

ChrootEveryone yes



# If the previous option is set to "no", members of the following group
# won't be restricted. Others will be. If you don't want chroot()ing anyone,
# just comment out ChrootEveryone and TrustedGID.

# TrustedGID                   100



# Turn on compatibility hacks for broken clients

BrokenClientsCompatibility no



# Maximum number of simultaneous users

MaxClientsNumber 250



# Run as a background process

Daemonize No



# Maximum number of simultaneous clients with the same IP address

MaxClientsPerIP 20



# If you want to log all client commands, set this to "yes".
# This directive can be specified twice to also log server responses.

VerboseLog yes

VerboseLog yes



# List dot-files even when the client doesn't send "-a".

DisplayDotFiles yes



# Disallow authenticated users - Act only as a public FTP server.

AnonymousOnly no



# Disallow anonymous connections. Only accept authenticated users.

NoAnonymous yes



# Syslog facility (auth, authpriv, daemon, ftp, security, user, local*)
# The default facility is "ftp". "none" disables logging.

SyslogFacility ftp,auth,authpriv,daemon,security,user



# Display fortune cookies

# FortunesFile                 /usr/share/fortune/zippy



# Don't resolve host names in log files. Recommended unless you trust
# reverse host names, and don't care about DNS resolution being possibly slow.

DontResolve yes



# Maximum idle time in minutes (default = 15 minutes)

MaxIdleTime 15



# LDAP configuration file (see README.LDAP)

# LDAPConfigFile               /etc/pureftpd-ldap.conf



# MySQL configuration file (see README.MySQL)

# MySQLConfigFile              /etc/pureftpd-mysql.conf


# PostgreSQL configuration file (see README.PGSQL)

# PGSQLConfigFile              /etc/pureftpd-pgsql.conf


# PureDB user database (see README.Virtual-Users)

# PureDB                       /etc/pureftpd.pdb


# Path to pure-authd socket (see README.Authentication-Modules)

ExtAuth /var/run/ftpd.sock



# If you want to enable PAM authentication, uncomment the following line

# PAMAuthentication            yes



# If you want simple Unix (/etc/passwd) authentication, uncomment this

# UnixAuthentication           yes



# Please note that LDAPConfigFile, MySQLConfigFile, PAMAuthentication and
# UnixAuthentication can be used specified once, but can be combined
# together. For instance, if you use MySQLConfigFile, then UnixAuthentication,
# the SQL server will be used first. If the SQL authentication fails because the
# user wasn't found, a new attempt will be done using system authentication.
# If the SQL authentication fails because the password didn't match, the
# authentication chain stops here. Authentication methods are chained in
# the order they are given.



# 'ls' recursion limits. The first argument is the maximum number of
# files to be displayed. The second one is the max subdirectories depth.

LimitRecursion 10000 8



# Are anonymous users allowed to create new directories?

AnonymousCanCreateDirs no



# If the system load is greater than the given value, anonymous users
# aren't allowed to download.

MaxLoad 4



# Port range for passive connections - keep it as broad as possible.

PassivePortRange 49152 65534



# Force an IP address in PASV/EPSV/SPSV replies. - for NAT.
# Symbolic host names are also accepted for gateways with dynamic IP
# addresses.

# ForcePassiveIP 5.9.161.221




# Upload/download ratio for anonymous users.

# AnonymousRatio               1 10



# Upload/download ratio for all users.
# This directive supersedes the previous one.

# UserRatio                    1 10



# Disallow downloads of files owned by the "ftp" system user;
# files that were uploaded but not validated by a local admin.

AntiWarez yes



# IP address/port to listen to (default=all IP addresses, port 21).

Bind 21



# Maximum bandwidth for anonymous users in KB/s

# AnonymousBandwidth           8



# Maximum bandwidth for *all* users (including anonymous) in KB/s
# Use AnonymousBandwidth *or* UserBandwidth, not both.

# UserBandwidth                8



# File creation mask. <umask for files>:<umask for dirs> .
# 177:077 if you feel paranoid.

Umask 133:022



# Minimum UID for an authenticated user to log in.
# For example, a value of 100 prevents all users whose user id is below
# 100 from logging in. If you want "root" to be able to log in, use 0.

MinUID 100



# Allow FXP transfers for authenticated users.

AllowUserFXP no



# Allow anonymous FXP for anonymous and non-anonymous users.

AllowAnonymousFXP no



# Users can't delete/write files starting with a dot ('.')
# even if they own them. But if TrustedGID is enabled, that group
# will exceptionally have access to dot-files.

ProhibitDotFilesWrite no



# Prohibit *reading* of files starting with a dot (.history, .ssh...)

ProhibitDotFilesRead no



# Don't overwrite files. When a file whose name already exist is uploaded,
# it gets automatically renamed to file.1, file.2, file.3, ...

AutoRename no



# Prevent anonymous users from uploading new files (no = upload is allowed)

AnonymousCantUpload yes



# Only connections to this specific IP address are allowed to be
# non-anonymous. You can use this directive to open several public IPs for
# anonymous FTP, and keep a private firewalled IP for remote administration.
# You can also only allow a non-routable local IP (such as 10.x.x.x) for
# authenticated users, and run a public anon-only FTP server on another IP.

# TrustedIP                    10.1.1.1



# To add the PID to log entries, uncomment the following line.

# LogPID                       yes



# Create an additional log file with transfers logged in a Apache-like format :
# fw.c9x.org - jedi [13/Apr/2017:19:36:39] "GET /ftp/linux.tar.bz2" 200 21809338
# This log file can then be processed by common HTTP traffic analyzers.

AltLog xferlog:/etc/apache2/logs/domlogs/ftpxferlog



# Create an additional log file with transfers logged in a format optimized
# for statistic reports.

AltLog                       stats:/var/log/pureftpd.log



# Create an additional log file with transfers logged in the standard W3C
# format (compatible with many HTTP log analyzers)

# AltLog                       w3c:/var/log/pureftpd.log



# Disallow the CHMOD command. Users cannot change perms of their own files.

# NoChmod                      yes



# Allow users to resume/upload files, but *NOT* to delete them.

# KeepAllFiles                 yes



# Automatically create home directories if they are missing

# CreateHomeDir                yes



# Enable virtual quotas. The first value is the max number of files.
# The second value is the maximum size, in megabytes.
# So 1000:10 limits every user to 1000 files and 10 MB.

# Quota                        1000:10



# If your pure-ftpd has been compiled with standalone support, you can change
# the location of the pid file. The default is /var/run/pure-ftpd.pid

# PIDFile                      /var/run/pure-ftpd.pid



# If your pure-ftpd has been compiled with pure-uploadscript support,
# this will make pure-ftpd write info about new uploads to
# /var/run/pure-ftpd.upload.pipe so pure-uploadscript can read it and
# spawn a script to handle the upload.
# Don't enable this option if you don't actually use pure-uploadscript.

# CallUploadScript             yes



# This option is useful on servers where anonymous upload is
# allowed. When the partition is more that percententage full,
# new uploads are disallowed.

MaxDiskUsage 99



# Set to 'yes' to prevent users from renaming files.

# NoRename                     yes



# Be 'customer proof': forbids common customer mistakes such as
# 'chmod 0 public_html', that are valid, but can cause customers to
# unintentionally shoot themselves in the foot.

CustomerProof yes



# Per-user concurrency limits. Will only work if the FTP server has
# been compiled with --with-peruserlimits.
# Format is: <max sessions per user>:<max anonymous sessions>
# For example, 3:20 means that an authenticated user can have up to 3 active
# sessions, and that up to 20 anonymous sessions are allowed.

# PerUserLimits                3:20



# When a file is uploaded and there was already a previous version of the file
# with the same name, the old file will neither get removed nor truncated.
# The file will be stored under a temporary name and once the upload is
# complete, it will be atomically renamed. For example, when a large PHP
# script is being uploaded, the web server will keep serving the old version and
# later switch to the new one as soon as the full file will have been
# transferred. This option is incompatible with virtual quotas.

# NoTruncate                   yes



# This option accepts three values:
# 0: disable SSL/TLS encryption layer (default).
# 1: accept both cleartext and encrypted sessions.
# 2: refuse connections that don't use the TLS security mechanism,
#    including anonymous sessions.
# Do _not_ uncomment this blindly. Double check that:
# 1) The server has been compiled with TLS support (--with-tls),
# 2) A valid certificate is in place,
# 3) Only compatible clients will log in.

TLS 1


# Cipher suite for TLS sessions.
# The default suite is secure and setting this property is usually
# only required to *lower* the security to cope with legacy clients.
# Prefix with -C: in order to require valid client certificates.
# If -C: is used, make sure that clients' public keys are present on
# the server.

TLSCipherSuite HIGH



# Certificate file, for TLS

# CertFile                     /etc/ssl/private/pure-ftpd.pem



# Listen only to IPv4 addresses in standalone mode (ie. disable IPv6)
# By default, both IPv4 and IPv6 are enabled.

# IPV4Only                     yes



# Listen only to IPv6 addresses in standalone mode (i.e. disable IPv4)
# By default, both IPv4 and IPv6 are enabled.

# IPV6Only                     yes



# UTF-8 support for file names (RFC 2640)
# Set the charset of the server filesystem and optionally the default charset
# for remote clients that don't use UTF-8.
# Works only if pure-ftpd has been compiled with --with-rfc2640

# FileSystemCharset                big5
# ClientCharset                    big5