1.10. Setting the Wireless Regulatory Domain

In Red Hat Enterprise Linux, the crda package contains the Central Regulatory Domain Agent that provides the kernel with the wireless regulatory rules for a given jurisdiction. It is used by certain udev scripts and should not be run manually unless debugging udev scripts. The kernel triggers to run crda by sending a udev event upon a new regulatory domain change. Regulatory domain changes are triggered by the Linux wireless subsystem (IEEE-802.11). This subsystem uses the regulatory.bin file to keep its regulatory database information.
The setregdomain utility sets the regulatory domain for your system; it takes no arguments and is normally called through system script such as udev rather than manually by the administrator. If a country code look-up fails, the system administrator can define the COUNTRY environment variable in the /etc/sysconfig/regdomain file.
See the following man pages for more detailed information about the regulatory domain:
  • setregdomain(1) man page — set regulatory domain based on country code
  • crda(8) man page — send to the kernel a wireless regulatory domain for a given ISO or IEC 3166 alpha2
  • regulatory.bin(5) man page — The Linux wireless regulatory database
  • iw(8) man page — show or manipulate wireless devices and their configuration