[j-nsp] improving global unicast convergence (with or without BGP-PIC)

[adamv0025 at netconsultings.com]

> Of Alexander Arseniev
> Sent: Wednesday, April 19, 2017 11:51 AM
> - then 203.0.113.0 will appear as "indirect" and You can have the usual
INH
> benefits. Example from my lab:
> 
> show krt indirect-next-hop | find "203.0.113."
> 
> Indirect Nexthop:
> Index: 1048592 Protocol next-hop address: 203.0.113.0
>    RIB Table: inet.0
>    Policy Version: 1                     References: 1
>    Locks: 3                              0x9e54f70
>    Flags: 0x2
>    INH Session ID: 0x185
>    INH Version ID: 0
>    Ref RIB Table: unknown
>          Next hop: #0 0.0.0.0.0.0 via ae4.100
>          Session Id: 0x182
>        IGP FRR Interesting proto count : 1
>        Chain IGP FRR Node Num          : 1
>           IGP Resolver node(hex)       : 0xb892f54
>           IGP Route handle(hex)        : 0x9dc8e14      IGP rt_entry
> protocol        : Static
>           IGP Actual Route handle(hex) : 0x0            IGP Actual
> rt_entry protocol : Any
> 
> Disclaimer - I haven't tested the actual convergence with this setup.
> 
But what good is an indirect next-hop if it's pointing to just a single
forwarding next-hop??

Example of correctly programed backup NHs for a BGP route: 
...
#Multipath Preference: 255
Next hop: ELNH Address 0x585e1440 weight 0x1, selected  <<<eBGP primary path
Next hop: ELNH Address 0x370c8698 weight 0x4000               <<< PIC backup
via iBGP
  Indirect next hop: 9550000 1048589 INH Session ID: 0x605
     Next hop: 10.0.20.1 via ae1.0 weight 0x1 <<< IGP primary path
     Next hop: 10.0.10.1 via ae0.0 weight 0xf000 <<< LFA backup path

-I doubt you can get this with a static default route 

For the above you need to allow for multiple NHs to be programed into FIB
using:
set policy-options policy-statement ECMP then load-balance per-packet
set routing-options forwarding-table export ECMP

adam

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