I’m going through a really unusual problem with regard to IS-IS Interface Metric / Price calculation in Juniper MX. We now have configured a reference bandwidth of 1000G on all routers.This by definition means an ae interface (with 2 x 10G member Hyperlinks) would yield a price of 50G (1000G/20G = 50). We will see this utilizing command ‘present isis interface’ on Junos.
Nevertheless in my case , we now have two routers which might be immediately linked utilizing Bundle Hyperlink (AE Hyperlink) that has 2 x 10G member Hyperlinks. IS-IS is working between them. Now every router ought to have interface metric of fifty. However from CLI we see that R1 has interface metric of 33 ! whereas R2 has interface metric of fifty (which is right). So How R1 is saying interface metric is 33 when it has solely 2 x 10G member hyperlinks. (Price needs to be 50 whereas Junos is saying a metric of 33).
Junos on R1 is 13.3R7-S3.1 whereas on R2 it’s 15.1R6-S5. Each are MX960 sequence routers.
Many Thanks …
I now share CLI output to assist my question :-
<——————————R2——————————————->
R2> present lacp interfaces ae16
Aggregated interface: ae16
LACP state: Function Exp Def Dist Col Syn Aggr Timeout Exercise
xe-8/3/2 Actor No No Sure Sure Sure Sure Quick Lively
xe-8/3/2 Accomplice No No Sure Sure Sure Sure Quick Lively
xe-8/0/0 Actor No No Sure Sure Sure Sure Quick Lively
xe-8/0/0 Accomplice No No Sure Sure Sure Sure Quick Lively
LACP protocol: Obtain State Transmit State Mux State
xe-8/3/2 Present Quick periodic Accumulating distributing
xe-8/0/0 Present Quick periodic Accumulating distributing
R2> present configuration interfaces ae16
apply-groups [ xge-if-parameters ubfd-ae ];
description Related to R1;
aggregated-ether-options {
bfd-liveness-detection {
neighbor 192.168.0.38;
local-address 192.168.0.13;
}
lacp {
lively;
periodic quick;
}
}
unit 3 {
apply-groups core-ifl-parameters;
vlan-id 3;
household inet {
handle 10.10.20.2/30;
}
household mpls;
}
R2> present configuration protocols isis interface ae16.3
apply-groups isis-ifl-parameters-wo-bfd;
ldp-synchronization;
R2> present configuration protocols isis
inactive: traceoptions {
file isis-log;
flag state;
}
reference-bandwidth 1000g;
lsp-lifetime 65535;
stage 1 disable;
stage 2 {
authentication-key ""; ## SECRET-DATA
authentication-type md5;
wide-metrics-only;
}
interface ae27.3 {
apply-groups isis-ifl-parameters-wo-bfd;
ldp-synchronization;
}
interface ae29.3 {
apply-groups isis-ifl-parameters;
ldp-synchronization;
}
interface lo0.0;
R2> present isis interface ae16.3
IS-IS interface database:
Interface L CirID Degree 1 DR Degree 2 DR L1/L2 Metric
ae16.3 2 0x1 Disabled Level to Level 50/50
<——————————R1——————————————->
R1> present lacp interfaces ae16
Aggregated interface: ae16
LACP state: Function Exp Def Dist Col Syn Aggr Timeout Exercise
xe-0/2/9 Actor No No Sure Sure Sure Sure Quick Lively
xe-0/2/9 Accomplice No No Sure Sure Sure Sure Quick Lively
xe-8/0/6 Actor No No Sure Sure Sure Sure Quick Lively
xe-8/0/6 Accomplice No No Sure Sure Sure Sure Quick Lively
LACP protocol: Obtain State Transmit State Mux State
xe-0/2/9 Present Quick periodic Accumulating distributing
xe-8/0/6 Present Quick periodic Accumulating distributing
R1> present configuration interfaces ae16
apply-groups [ xge-if-parameters ubfd-ae ];
description Related to R2;
aggregated-ether-options {
bfd-liveness-detection {
neighbor 192.168.0.13;
local-address 192.168.0.38;
}
link-speed 10g;
lacp {
lively;
periodic quick;
}
}
unit 3 {
apply-groups core-ifl-parameters;
vlan-id 3;
household inet {
handle 10.10.20.1/30;
}
household iso;
}
R1> present configuration interfaces ae16.3
apply-groups core-ifl-parameters;
vlan-id 3;
household inet {
handle 10.10.20.1/30;
}
household iso;
R1> present configuration protocols isis
reference-bandwidth 1000g;
lsp-lifetime 65535;
spf-options {
delay 50;
holddown 5000;
rapid-runs 3;
}
stage 1 disable;
stage 2 {
authentication-key ""; ## SECRET-DATA
authentication-type md5;
wide-metrics-only;
}
interface ae16.3 {
apply-groups isis-ifl-parameters-wo-bfd;
ldp-synchronization;
}
}
interface ae45.3 {
apply-groups isis-ifl-parameters;
ldp-synchronization;
stage 2 metric 33;
}
interface ae46.3 {
apply-groups isis-ifl-parameters;
ldp-synchronization;
stage 2 metric 33;
}
interface lo0.0 {
passive;
}
R1> present isis interface ae16.3
IS-IS interface database:
Interface L CirID Degree 1 DR Degree 2 DR L1/L2 Metric
ae16.3 2 0x1 Disabled Level to Level 33/33
R1> present route 192.168.0.13
inet.0: 38694 locations, 113966 routes (38470 lively, 1 holddown, 226 hidden)
+ = Lively Route, - = Final Lively, * = Each
192.168.0.13/32 *[IS-IS/18] 1d 06:58:47, metric 33
> to 10.10.20.2 by way of ae16.3