This article provides information on how to configure the TED protocol to prefer one IGP over the other, when multiple IGP`s are configured for traffic engineering.
TED protocol preference can be influenced to prefer one IGP over the other via the following command :
set protocols traffic-engineering credibility-protocol-preference
Topology used:
lo0 192.168.1.1 lo0 192.168.1.2
+---------+ +---------+
| +----------------------+ |
| r1 |ge-0/2/0 ge-0/2/1| r2 |
+---------+10.1.2.1 10.1.2.2+---------+
- For illustration purposes, the r1 and r2 logical systems are used.
- Traffic engineering is enabled on both the ISIS and OSPF routing protocols.
- By default, ISIS is preferred as the TED protocol
- When a particular link`s information is populated in TED by both OSPF and ISIS, TED will prefer ISIS over OSPF, as by default, the credibility of ISIS is higher than that of OSPF.
- This selection occurs before the link`s traffic-engineering metric is evaluated or compared.
- Versions 9.6 and 10.0 or later work as described above. For versions before 9.6 / 10.0, TED credibility is not enforced.
- The default credibility/protocol preference can be changed to prefer one protocol over the other, by using the set protocols <protocol> traffic-engineering credibility-protocol-preference hidden command.
Configuration – Logical system r1:
lab@black# show logical-systems r1
Jun 25 16:32:09
interfaces {
ge-0/2/0 {
unit 0 {
family inet {
address 10.1.2.1/24;
}
family iso;
}
}
lo0 {
unit 1 {
family inet {
address 192.168.1.1/32;
}
family iso {
address 49.0190.0192.0168.0101.00;
}
}
}
}
protocols {
isis {
interface ge-0/2/0.0;
interface lo0.1;
interface all {
level 2 disable;
}
}
ospf {
traffic-engineering;
area 0.0.0.0 {
interface all;
}
}
}
routing-options {
router-id 192.168.1.1;
}
Logical system r2 :
[edit]
lab@black# show logical-systems r2
Jun 25 16:32:13
interfaces {
ge-0/2/1 {
unit 0 {
family inet {
address 10.1.2.2/24;
}
family iso;
}
}
lo0 {
unit 2 {
family inet {
address 192.168.1.2/32;
}
family iso {
address 49.0190.0192.0168.0102.00;
}
}
}
}
protocols {
isis {
interface ge-0/2/1.0;
interface lo0.2;
interface all {
level 2 disable;
}
}
ospf {
traffic-engineering;
area 0.0.0.0 {
interface all;
}
}
}
routing-options {
router-id 192.168.1.2;
}
Outputs:
- By default, ISIS is preferred in TED.
- The show ted protocol command can be used to view the TED preference:
[edit] lab@black# run show ted protocol logical-system r1 Jun 25 16:32:42 Protocol name Credibility Self node IS-IS(2) 2 black-r1.00(192.168.1.1) < ISIS preferred, credibility 2 IS-IS(1) 1 black-r1.00(192.168.1.1) OSPF(0) 0 black-r1.00(192.168.1.1) [edit] lab@black# run show ted protocol logical-system r2 Jun 25 16:34:36 Protocol name Credibility Self node IS-IS(2) 2 black-r2.00(192.168.1.2) < ISIS preferred, credibility 2 IS-IS(1) 1 black-r2.00(192.168.1.2) OSPF(0) 0 black-r2.00(192.168.1.2)
Configuration change:
r1 is configured to prefer OSPF in TED, whereas r2 is left as is:
[edit] lab@black# set logical-systems r1 protocols ospf traffic-engineering credibility-protocol-preference
Configuration:
[edit]
lab@black# show logical-systems r1 protocols isis
Jun 25 16:33:57
interface ge-0/2/0.0;
interface lo0.1;
interface all {
level 2 disable;
}
[edit]
lab@black# show logical-systems r1 protocols ospf
Jun 25 16:34:01
traffic-engineering credibility-protocol-preference; < Configured
area 0.0.0.0 {
interface all;
}
Outputs:
[edit] lab@black# run show ted protocol logical-system r1 Jun 25 16:34:20 Protocol name Credibility Self node OSPF(0) 502 black-r1.00(192.168.1.1)< OSPF is preferred in TED, credibility 502 IS-IS(2) 2 black-r1.00(192.168.1.1) IS-IS(1) 1 black-r1.00(192.168.1.1) [edit] lab@black# run show ted protocol logical-system r2 Jun 25 16:34:21 Protocol name Credibility Self node IS-IS(2) 2 black-r2.00(192.168.1.2)< ISIS is preferred in TED, as r2`s configuration was not changed IS-IS(1) 1 black-r2.00(192.168.1.2) OSPF(0) 0 black-r2.00(192.168.1.2)