On the module's main page, click on the Limits and Access Control icon. The form shown in Figure 41.4 will appear in your browser.

The Concurrent user limits table is where limits on the number of connections can be entered. Each row defines a limit that applies to a certain class at certain times. As usual with tables in this module, there will be one empty row at the bottom for adding a new limit (and if this is the first one, the table will only contain that one row). Existing limits can be edited by changing their fields in the table or deleted by selecting the Empty option from the class menu.

The fields in each row should be filled in as follows:

Apply to class You must select the name of the class to which this limit will apply from the menu. Multiple limits can be defined for the same class at different times.

Maximum users To set a limit for the chosen class, select the second radio button and enter the maximum number of concurrent connections into the adjacent text box. If the Unlimited button is selected, no limit will apply to the class at the specified times. For example, you could add a row that turns off restrictions at night above another row that sets them for the entire day.

At times If Any time is selected, the limit will apply all the time. If you choose the second option and enter a UUCP-style time specification into the text box, however, only connections made during that period will be restricted. For example, Any0900-1700 means 9am to 5pm every day; Mo,Tu,We means Mondays, Tuesdays, and Wednesdays; Wk means weekdays; and Wk1700-0900,Sa,Su means times outside office hours.

WU-FTPD always checks the table in descending order for an entry that matches a connecting client's class and the current time, and stops when it finds one. This means that entries that specify times (such as Any0900-1700) should be placed above those that have Any time selected, so that the specific entry is actually used when appropriate.

Error message file This is the full path to a file containing a message that will be sent to clients whose connections exceed the limit. This should explain why they are being rejected and suggest other times or FTP servers to try.

Hit the Save button at the bottom of the page to activate the connection limits. To add more than one, you will need to revisit the form so that a new blank row appears in the table.