[j-nsp] BGP Extended Community sub-type as zero not valid

[Olivier Benghozi]

Technically, AS0 is invalid (RFC 7607, but it was stated before that more or less clearly).

However on JunOS you may fill the first field of an rt with 0 by using the IPv4:value format for rt (type 1):
target:0.0.0.0:1

..but you will be limited to 16 bits for the other field (so up to 65535).


> Le 8 févr. 2019 à 21:40, heisenbug at xpto <heisenbug at xpto.eng.br> a écrit :
> 
> I'm doing some tests with Juniper devices (srx, vmx, vrr, ptx, mx) (from junos 15 to 18) and the result are the same, maybe is something that I'm not seeing. The purposed environment for test:
> 
> AS2222(2bytes) <-> AS222222(4bytes)
> 
> AS2222 is announcing the network 172.255.255.0 and setting the ext community rt:1:222222(for lab purpose). For example(this is working):
> AS222222# run show route protocol bgp extensive
> 
> inet.0: 5 destinations, 5 routes (5 active, 0 holddown, 0 hidden)
> 172.255.255.0/24 (1 entry, 1 announced)
> TSI:
> KRT in-kernel 172.255.255.0/24 -> {172.0.0.1}
>         *BGP    Preference: 170/-101
>                 Next hop type: Router, Next hop index: 524
>                 Address: 0xb3a1030
>                 Next-hop reference count: 2
>                 Source: 172.0.0.1
>                 Next hop: 172.0.0.1 via em1.0, selected
>                 Session Id: 0x0
>                 State: <Active Ext>
>                 Local AS: 222222 Peer AS:  2222
>                 Age: 3:43
>                 Validation State: unverified
>                 Task: BGP_2222.172.0.0.1
>                 Announcement bits (1): 0-KRT
>                 AS path: 2222 I
>                 Communities: target:1:222222
>                 Accepted
>                 Localpref: 100
>                 Router ID: 172.0.0.1
> 
> But if I try to set the sub-type as 0 (zero), Juniper dons't accept (https://tools.ietf.org/rfc/rfc4360.txt).
> 
> 
> [edit]
> AS2222# delete policy-options community TEST
> 
> [edit]
> AS2222# set policy-options community TEST members target:0:222222
> 
> [edit]
> AS2222# show | compare
> [edit policy-options community TEST]
> -   members target:1:222222;
> +   members target:0:222222;
> 
> [edit]
> AS2222# commit
> [edit policy-options community TEST]
>   'members target:0:222222'
>     invalid autonomous system value at '0' not in range 1 to 65535. Use '0L' Long format to specify 4 byte AS
> error: configuration check-out failed
> 
> [edit]
> AS2222# delete policy-options community TEST
> 
> [edit]
> AS2222# set policy-options community TEST members target:0L:222222
> 
> [edit]
> AS2222# show | compare
> [edit policy-options community TEST]
> -   members target:1:222222;
> +   members target:0L:222222;
> 
> [edit]
> AS2222# commit
> [edit policy-options community TEST]
>   'members target:0L:222222'
>     invalid autonomous system value at '0' not in range 1 to 4294967295
> error: configuration check-out failed
> 
> [edit]
> 
> Anyone have any idea about? There's another way to do that? I need to use zero on this case and other bgp daemons/vendors allow to do that.
> 
> Thanks in advance.