The multipath was not working inside routing-instance even after adding knob globally.
root@JTAC> show configuration protocols bgp | match mult
multipath;
|
root@JTAC> show route forwarding-table destination a.b.c.d table TEST
<snip>
Destination Type RtRef Next hop Type Index NhRef Netif
a.b.c.d user 0 ulst 1048691 2
w.x.y.z ucst 656 4 et-0/0/0.100
The multipath is activated only in global table & availabled in all associated BGP groups globally.
But the same to work inside the vrf or instance table, the knob must be defined inside the routing instance.
The below document on multipath configuration do not explicitly mention about the knob addition inside instance config.
https://www.juniper.net/documentation/us/en/software/junos/cli-reference/topics/ref/statement/multipath-edit-protocols-bgp.html
Hence the purpose of this KB is to ensure that we need the knob inside the routing instance, were the multipath is to be availed to the routes in its table.
With multipath knob added in global BGP config:
root@JTAC> show route forwarding-table destination a.b.c.d table TEST extensive
Nexthop: w.x.y.z
Next-hop type: unicast Index: 915 Reference: 3
Next-hop interface: et-0/0/0.100
root@JTAC> show route a.b.c.d table TEST.inet.0 extensive
>snip>
Inactive reason: Not Best in its group - Active preferred
With multipath knob added in instance's BGP config:
root@JTAC# set routing-instances TEST protocols bgp multipath
w.x.y.x ucst 659 4 et-0/0/1.200