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. This allows for a seamless AS based on ISO NSAPs.
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NOTE: CLNS is supported for the J-series Services Router only. |
A single routing domain consisting of ISO NSAP devices are considered to be CLNS islands. CLNS islands are connected together by VPNs.
You can configure BGP to exchange ISO CLNS routes between PE routers connecting various CLNS islands in a VPN using multiprotocol BGP extensions. These extensions are the ISO VPN NLRIs.
To enable MBGP to carry CLNS VPN NLRIs, include the iso-vpn statement:
iso-vpn {
unicast {
prefix-limit number;
rib-group group-name;
}
}
To limit the number of prefixes from a peer, include the prefix-limit statement. To specify a routing table group, include the rib-group statement.
For a list of hierarchy levels at which you can configure this statement, see the statement summary section for this statement.
Each CLNS network island is treated as a separate VRF instance on the PE router.
You can configure CLNS on the global level, group level, and neighbor level.
For information on CLNS, see Configuring Support for Connectionless Network Services and the J-series Services Router Advanced WAN Access Configuration Guide.
Example: Enabling CLNS Between Two Routers
Configure CLNS between two routers through a route reflector:
On Router 1:
[edit protocols bgp]
protocols {
bgp {
local-address 10.255.245.195;
group pe-pe {
type internal;
neighbor 10.255.245.194 {
family iso-vpn {
unicast;
}
}
}
}
}
[edit routing-instances]
routing-instances {
aaaa {
instance-type vrf;
interface fe-0/0/0.0;
interface so-1/1/0.0;
interface lo0.1;
route-distinguisher 10.255.245.194:1;
vrf-target target:11111:1;
protocols {
isis {
export dist-bgp;
no-ipv4-routing;
no-ipv6-routing;
clns-routing;
interface all;
}
}
}
}
On Router 2:
[edit protocols bgp]
protocols {
bgp {
group pe-pe {
type internal;
local-address 10.255.245.198;
family route-target;
neighbor 10.255.245.194 {
family iso-vpn {
unicast;
}
}
}
}
}
[edit routing-instances]
routing-instances {
aaaa {
instance-type vrf;
interface lo0.1;
interface so-0/1/2.0;
interface so-0/1/3.0;
route-distinguisher 10.255.245.194:1;
vrf-target target:11111:1;
routing-options {
rib aaaa.iso.0 {
static {
iso-route 47.0005.80ff.f800.0000.bbbb.1022/104 next-hop 47.0005.80ff.f800.0000.aaaa.1000.1921.6800.4196.00;
}
}
}
protocols {
isis {
export dist-bgp;
no-ipv4-routing;
no-ipv6-routing;
clns-routing;
interface all;
}
}
}
}
On Route Reflector:
[edit protocols bgp]
protocols {
bgp {
group pe-pe {
type internal;
local-address 10.255.245.194;
family route-target;
neighbor 10.255.245.195 {
cluster 0.0.0.1;
}
neighbor 10.255.245.198 {
cluster 0.0.0.1;
}
}
}
}
Example: Configuring CLNS Within a VPN
Configure CLNS on three PE routers within a VPN:
On PE Router 1:
[edit protocols bgp]
protocols {
mpls {
interface all;
}
bgp {
group asbr {
type external;
local-address 10.245.245.3;
neighbor 10.245.245.1 {
multihop;
family iso-vpn {
unicast;
}
peer-as 200;
}
}
}
}
[edit routing-instances]
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;
}
}
}
}
On PE Router 2:
[edit protocols bgp]
protocols {
bgp {
group asbr {
type external;
multihop;
local-address 10.245.245.1;
family iso-vpn {
unicast;
}
neighbor 10.245.245.2 {
peer-as 300;
}
neighbor 10.245.245.3 {
peer-as 100;
}
}
}
}
[edit routing-instances]
routing-instances {
aaaa {
instance-type vrf;
interface lo0.1;
route-distinguisher 10.245.245.1:1;
vrf-target target:11111:1;
}
}
On PE Router 3:
[edit protocols bgp]
protocols {
bgp {
group asbr {
type external;
multihop;
local-address 10.245.245.2;
neighbor 10.245.245.1 {
family iso-vpn {
unicast;
}
peer-as 200;
}
}
}
}
[edit routing-instances]
routing-instances {
aaaa {
instance-type vrf;
interface lo0.1;
interface fe-0/0/1.0;
interface t1-3/0/0.0;
route-distinguisher 10.245.245.1:1;
vrf-target target:11111:1;
protocols {
isis {
export dist-bgp;
no-ipv6-routing;
clns-routing;
interface all;
}
}
}
}
