The max-users option specifies the maximum number of users (both anonymous and non-anonymous) that are allowed to be using the FTP server simultaneously.  As a consequence, this limits the number of ncftpd processes that are running on your server.

For example, if you use max-users=50, there will be up to 52 ncftpd processes running at any one time; one for each user, a logger process and a main process. There could also be other processes created by NcFTPd if you enable the on-the-fly TAR feature.

The number of users to use for max-users varies for each site, but you shouldn't use a number higher than your system could handle.  I.e., if your system can't handle 1000 active processes, don't set max-users to 1000 :-)

Examples:

max-users=250
max-users=50
max-users=10

• min-users