When connecting to a server, this variable is checked versus the number of servers currently connected to the ircnet. If the number of servers is less than the setting of MINIMUM_SERVERS, you will automatically be disconnected from that server and IRCII will attempt to connect to the next server in you server list (as though you had done SERVER +). This is useful if the net is fragmented to keep you on a more populated portion of the net. This will be rechecked if you issue a lusers. This will only affect your primary server. Secondary servers are not checked vs this variable.
See Also: set/minimum_users server lusers ircii/server_lists