How-To Increase the amount of clients that can connect simultaneously in proftpd.

Introduction

This article is intended to demonstrate how to increase the maxclients allowed simultaneously when using proftpd as an FTP server. 

The MaxClients directive configures the maximum number of authenticated clients which may be logged into a server or anonymous account. Once this limit is reached, additional clients attempting to authenticate will be disconnected. The special value none may be supplied, which removes all maximum connection limits from the applicable configuration context. Additionally, an optional message argument may be used, which will be displayed to a client attempting to exceed the maximum value; immediately before disconnection. The message argument is parsed for the magic string "%m", which is replaced with the configured maximum value. If a message is not supplied, a system-wide default message is used. Example: MaxClients 5 "Sorry, the maximum number of allowed users are already connected (%m)" Results in: 530 Sorry, the maximum number of allowed users are already connected (5)

Useful Links

How to edit a file via the command line. 

Max Clients Documentation proftpd.org 

Procedure

1. Log into your server via ssh using the root user.

2. Open the /etc/pureftpd.conf file via nano, vim, vi, etc.

3. Locate the 'MaxClients' Directive for the server in question.

<VirtualHost 172.16.1.15>
ServerName ftp.example.dom
AuthUserFile /etc/proftpd/example
MaxClients 3 "Sorry, this ftp server has reached its maximum user count (%m). Please try again later"
DirFakeGroup On ftpgroup
DirFakeUser On ftpuser
DefaultRoot ~

4. Increase the MaxClients Directive to the intended number.

<VirtualHost 172.16.1.15>
ServerName ftp.example.dom
AuthUserFile /etc/proftpd/example
MaxClients 10 "Sorry, this ftp server has reached its maximum user count (%m). Please try again later"
DirFakeGroup On ftpgroup
DirFakeUser On ftpuser
DefaultRoot ~

5. Restart the service, this can be done by using the /scripts/setupftpserver script as follows.

 /scripts/setupftpserver proftpd