Connectionless Network Services (CLNS) is a Layer 3 protocol, similar to Internet Protocol Version 4 (IPv4). CLNS uses network service access points (NSAPs) to address end systems and intermediate systems.
You can use IS-IS as the IGP to carry ISO CLNS routes through a network.
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Note: CLNS is supported for the J-series Services Router only. |
To enable IS-IS to exchange CLNS routes, include the clns-routing statement:
-
clns-routing;
For a list of hierarchy levels at which you can configure this statement, see the statement summary section for this statement.
You can configure a pure CLNS network by disabling IPv4 and IPv6 for IS-IS.
To disable IPv4, include the no-ipv4-routing statement:
-
no-ipv4-routing;
To disable IPv6, include the no-ipv6-routing statement:
-
no-ipv6-routing;
For a list of hierarchy levels at which you can configure these statements, see the statement summary section for these statements.
You can export BGP routes into Layer 2 IS-IS by configuring an export policy and applying the policy to IS-IS. You can export BGP routes from a specific VRF instance into IS-IS by configuring and applying an export policy at the [edit routing-instance instance-name protocols isis] hierarchy level. ES-IS routes from one routing instance cannot be exported into a Layer 1 IS-IS area of another routing instance.
To configure an export policy to export BGP routes into IS-IS, include the policy-statement statement:
- policy-statement policy-name {
-
- from {
- protocol bgp;
- family iso;
- }
-
- then {
- accept;
- }
- }
To apply an export policy, include the export statement at the [edit protocols isis] hierarchy level:
- export policy-name;
For a list of hierarchy levels at which you can configure this statement, see the statement summary section for these statements.
For more information on policy configuration, see the JUNOS Policy Framework Configuration Guide.
You can also export routes from protocols other than BGP into IS-IS. ES-IS routes are exported to IS-IS by default. You can export ES-IS routes into IS-IS by configuring a routing policy.
For information on CLNS, see the J-series Services Router Advanced WAN Access Configuration Guide.
Configure a routing policy to accept CLNS routes:
- policy-options {
-
- policy-statement dist-bgp {
-
- from {
- protocol bgp;
- family iso;
- }
- then accept;
- }
-
- policy-statement dist-static {
-
- from {
- protocol static;
- family iso;
- }
- then accept;
- }
- }
Configure CLNS for IS-IS:
- protocols {
-
- isis {
-
- traceoptions {
- file isis size 5m world-readable;
- flag error;
- }
- export dist-static;
- no-ipv6-routing;
- no-ipv4-routing;
- clns-routing;
- interface fe-0/0/1.0;
- interface t1-0/2/1.0;
-
- interface fxp0.0 {
- disable;
- }
- interface lo0.0;
- }
- }
Configure a routing instance that supports CLNS routes:
- routing-instances {
-
- aaaa {
- instance-type vrf;
- interface lo0.1;
- interface t1-3/0/0.0;
- interface fe-5/0/1.0;
- route-distinguisher 10.245.245.1:1;
- vrf-target target:11111:1;
-
- protocols {
-
- isis {
- export dist-bgp;
- no-ipv4-routing;
- no-ipv6-routing;
- clns-routing;
- interface all;
- }
- }
- }
- }