public List<IPAddress> getBypassHosts() throws GuacamoleException {
        return environment.getProperty(DUO_BYPASS_HOSTS, Collections.emptyList());
    }
Returns the list of IP addresses and subnets defined in guacamole.properties
for which Duo MFA should _not_ be enforced. Users logging in from hosts
contained in this list will be logged in without the MFA requirement.

@return
    A list of IP addresses and subnets for which Duo MFA should not be
    enforced.

@throws GuacamoleException 
    If guacamole.properties cannot be parsed, or if an invalid IP address
    or subnet is specified.
extensions/guacamole-auth-duo/src/main/java/org/apache/guacamole/auth/duo/conf/ConfigurationService.java