KRB5.CONF (man5)

krb5.conf − Kerberos configuration file The krb5.conf file contains Kerberos configuration information, including the locations of KDCs and admin servers for the Kerberos realms of interest, defaults for the current realm and for Kerberos applications, and mappings of hostnames onto Kerberos realms. Normally, you should install your krb5.conf file in the directory /etc. You can override the default location by setting the environment variable KRB5_CONFIG. Multiple colon−separated filenames may be specified in KRB5_CONFIG; all files which are present will be read. Starting in release 1.14, directory names can also be specified in KRB5_CONFIG; all files within the directory whose names consist solely of alphanumeric characters, dashes, or underscores will be read.