IS-IS Configuration Guidelines

To configure Intermediate System to Intermediate System (IS-IS), you include statements at the [edit protocols isis] hierarchy level of the configuration. Because IS-IS uses International Organization for Standardization (ISO) addresses, the JUNOS configurations for the IPv6 and IPv4 versions of IS-IS are identical. You can include the following statements in the configuration:

protocols {

    isis {

        disable;

        authentication-key key ;

        authentication-type authentication ;

        export [  policy-names  ]; 

        graceful-restart {

            disable;

        }

        level name  level level metric metric;

        level level-number { 

            authentication-key key ;

            authentication-type authentication ;

            external-preference preference ; 

            preference preference ; 

            wide-metrics-only; 

        }

        lsp-lifetime seconds ;

        no-authentication-check; 

        overload < timeout seconds >;

        reference-bandwidth reference-bandwidth;

        rib-group group-name;

        spf-delay milliseconds;

        }

        traceoptions {

            file name <replace> <size size> <files number > <no-stamp> 

                <(world-readable | no-world-readable)>;

            flag flag <flag-modifier> <disable>; 

        }

        interface interface-name {

            disable;

            authentication-key key ;

            authentication-type authentication ;

            csnp-interval (seconds  | disable);

            hello-authentication-key key ;

            hello-authentication-type authentication ;

            lsp-interval milliseconds ; 

            mesh-group (value | blocked); 

            passive; 

            level level-number { 

                disable;

                authentication-key key ;

                authentication-type authentication ;

                hello-authentication-key key ;

                hello-authentication-type authentication ;

                hello-interval seconds ; 

                hold-time seconds ; 

                metric metric ; 

                passive;

                priority number ; 

                te-metric metric ;

            }

        }

    }

}

By default, IS-IS is enabled for Level 1 and Level 2 routers on all interfaces on which an ISO address is configured.

This chapter discusses the following topics that provide information about configuring IS-IS:

• Minimum IS-IS Configuration
• Configure IS-IS Authentication
• Configure Interface-Specific Properties
• Configure the CSNP Interval
• Configure Mesh Groups
• Modify the Interface Metric
• Enable Wide Metrics for Traffic Engineering
• Configure Route Preferences
• Configure IS-IS Levels on an Interface
• Install Default Route toward Nearest Level 1/Level 2 Router
• Modify the LSP Interval
• Modify the LSP Lifetime
• Configure the Router to Appear Overloaded
• Configure the SPF Delay
• Disable Graceful Restart
• IS-IS and Multipoint Configurations
• Disable IS-IS on the Router
• Configure IS-IS Routing Policy
• Trace IS-IS Protocol Traffic
• IS-IS Configuration Example