You can limit the number of users that can log on to the host at one time using the settings described here.
To set the maximum number of users:
Important: While limits are configured per host, they are enforced per protocol. If a host has two listeners associated with it, one FTP and one SSH, then the host will permit the maximum number of users and anonymous users to connect for each protocol. If Max number of connections is set to 10, for example, then the host will permit 10 users to connect via FTP and 10 via SSH (for a potential maximum of 20).
If a host has multiple listeners of the same protocol type, the limits are still enforced by protocol. For example, if a host has 3 SSH listeners and 2 FTP listeners, it will permit only 10 total FTP users and 10 total SSH listeners (for a potential maximum of 20) to connect concurrently.
Note: If the user limit is exceeded, a system administrator or host administrator can still log on using the Ipswitch Web Admin. Also, a system administrator can always log on using a client.
Entering zero for either option disables new connections. This provides a way to temporarily shut off access to the host, so you can update files. New connections are not allowed, but current connections will continue until the user logs off, the connection exceeds the timeout value, or the connection is terminated by an administrator. Setting Max number of connections to zero disables any new connections; setting Max number of anonymous connections to zero disables only new anonymous connections.