The content of the file is a line of the following form:
/dev/tty /dev/kd/kd maxnum [startnum]
By default, maxnum is set to the maximum of 15. This specifies that VTs /dev/vt00 through dev/vt14 are available for use. Valid values for maxnum are in the range 1-15.
By default, startnum is set to 1. This specifies that VTs begin numbering at 1 (that is, /dev/vt00 is VT1). If there is no fourth argument, then VTs begin numbering at 0.
System resources are not actually consumed until a VT is opened, and the resources are released when it is closed. To save system resources you can reduce the number of VTs available. Do this by editing this file and changing maxnum to the number of VTs desired. The system must be rebooted before the new value of maxnum takes effect.