You first set a channel to be a master channel, then you set the parameters under which users will be allowed to join sub channels. You have a Maximum, Minimum and Limit that make up the basic commands. They work as follows:
The first users that try to join the Master channel will join a sub channel called #channel.1 (channel being whatever channel name the master channel is). They will continue to join until the channel LIMIT has been reached. When the LIMIT is reached the users will start to join #channel.2 etc. Users can join #channel.1 or any sub channel directly until the MAX setting has been reached. Users will always join the lowest number channel that has less users than the LIMIT that has been set. When users start to leave and the number of users drops to that set by MIN then the channel will look for an opportunity to compact. Compaction occurs when a lower number channel has a quantity of users in it that is less then the LIMIT minus the number of users that will be joined when the channel compacts. The compaction will look to both channels that are compacting as if users have just joined the channel.
All modes and topics that are set in the MASTER channel will be set in all sub channels. This way you can set all of the channels to moderated or any other mode at one time.
/mode #<channel> +l 30
/set #<channel> MASTER
/set #<channel> MAX 40
/set #<channel> MIN 10 /set #<channel> MASTER 0
With the above settings, when the channel hits 30 a new channel will be created. When the channel reaches 10 the channels will compact into the next lowest available room. New channels will be called .1 .2 etc. You can join a room until you hit the MAX number at which time you will get a channel full message.
MASTER 0 turns off Master/Slave channels and returns all the channels to being separately controlled.