<configuration>
    <authentication-client xmlns="urn:elytron:1.0">
        <authentication-rules>
            <rule use-configuration="configuration1">
                <match-host name="localhost" />
            </rule>
            <rule use-configuration="configuration1">
                <match-host name="127.0.0.1" />
            </rule>
       </authentication-rules>
        <authentication-configurations>
            <configuration name="configuration1">
                <allow-sasl-mechanisms names="DIGEST-MD5" />
                 <use-service-loader-providers />
                 <set-user-name name="user1" />
                 <credentials>
                     <clear-password password="password123" />
                 </credentials>
                 <set-mechanism-realm name="exampleManagementRealm" />
             </configuration>
        </authentication-configurations>
    </authentication-client>
</configuration>

$ ./jboss-cli.sh -Dwildfly.config.url=/path/to/custom-config.xml --controller=remote+http://localhost:9990 --no-local-auth -c

Authenticating against security realm: exampleManagementRealm
Username: