[j-nsp] QFX5100 and BGP graceful-shutdown in 19.1

[Sebastian Wiesinger]

Hi,

JunOS 19.1 brings support for the BGP graceful shutdown mechanism
(RFC8326):

https://tools.ietf.org/html/rfc8326

https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration-statement/graceful-shutdown-edit-protocols-bgp.html

While you could always do this by hand I was happy to see it
implemented in the platform because it might simplify policy handling.

I tried it on QFX5100 but couldn't get it to work. While the sender
part seems okay (set protocols bgp graceful-shutdown sender adds the
community to all outgoing routes), the receiver part does not work.

set protocols bgp graceful-shutdown receiver

does nothing on my setup. I tried to specify it in every BGP group
which did do nothing and I tried to explicitly set it to local-pref 0
which also does nothing.

Support for the feature is advertised in the group overview:

> show bgp group spines detail 
Group Type: External                               Local AS: 4200100001
  Name: spines          Index: 0                   Flags: <Export Eval>
  Export: [ bgp-redist-direct bgp-redist-from-upstream deny-everything ] 
  Options: <GracefulShutdownRcv>
  Holdtime: 0
  Graceful Shutdown Receiver local-preference: 0
  Total peers: 2        Established: 2
  172.25.1.0+179
  172.25.2.0+179
  Route Queue Timer: unset Route Queue: empty
  Table inet.0
    Active prefixes:              6
    Received prefixes:            6
    Accepted prefixes:            6
    Suppressed due to damping:    0
    Advertised prefixes:          2

But routes are unaffected:

> show route 10.210.128.128/25 detail 

inet.0: 13 destinations, 16 routes (13 active, 0 holddown, 0 hidden)
10.210.128.128/25 (2 entries, 1 announced)
        *BGP    Preference: 170/-101
                Next hop type: Router, Next hop index: 0
                Address: 0xba56a10
                Next-hop reference count: 4
                Source: 172.25.2.0
                Next hop: 172.25.1.0 via et-0/0/48.0
                Session Id: 0x0
                Next hop: 172.25.2.0 via et-0/0/49.0, selected
                Session Id: 0x0
                State: <Active Ext>
                Local AS: 4200100001 Peer AS: 4200100000
                Age: 19:55 
                Validation State: unverified 
                Task: BGP_4200100000.172.25.2.0
                Announcement bits (3): 0-KRT 1-BGP_RT_Background 2-BGP_RT_Background 
                AS path: 4200100000 4200100002 I 
                Accepted Multipath
                Localpref: 100
                Router ID: 172.25.255.2
         BGP    Preference: 170/-101
                Next hop type: Router, Next hop index: 1739
                Address: 0xba25c90
                Next-hop reference count: 4
                Source: 172.25.1.0
                Next hop: 172.25.1.0 via et-0/0/48.0, selected
                Session Id: 0x0
                State: <Ext Changed>
                Inactive reason: Active preferred
                Local AS: 4200100001 Peer AS: 4200100000
                Age: 10:41 
                Validation State: unverified 
                Task: BGP_4200100000.172.25.1.0
                AS path: 4200100000 4200100002 I 
>>>>>           Communities: graceful-shutdown
                Accepted MultipathContrib
>>>>>           Localpref: 100
                Router ID: 172.25.255.1

Has anyone else tested this?

Regards

Sebastian

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