Question regarding an unreachable protocol

[Irene Lalioti]

Thanks a lot Alexander for your feedback! I have direct protocol
disabled all along like this

protocol direct {
        disabled;               # Disable by default
        ipv6;                   # Connect to default IPv6 table
}

and also the local route in the table :

-bash-4.2# ip -6 route show table 60 | grep 2001:7f8:4c::/64
2001:7f8:4c::/64 dev peering metric 1024 pref medium

.. So then I may need to define there these routes..

Have a nice day!

irene

On 18/03/2020 15:52, Alexander Zubkov wrote:
> Hi,
>
> Please check that you have direct interface routes in your bird's
> table. Probably the next hop in your bgp route is not directly
> reachable from the bird's point of view. You might need to add
> "protocol direct { ... }" for example. Or maybe you have not direct
> next hop in your routes.
> As far as I know, bird advertises such routes still, but if they
> marked unreachable - no matter how high localpref the have, other
> routes are preferred over it.
>
> On Wed, Mar 18, 2020 at 2:24 PM Irene Lalioti <irene.lalioti at restena.lu> wrote:
>> Hello dear Maria! Hello bird community!
>>
>> I have a question to ask you. We realized that there is one BGP session
>> which bird sees it as an unreachable destination, thus it doesn't
>> advertise its prefixes to the other peers, since it does not go to the
>> master table.
>>
>> We run v2.0.7 and hereby I paste some outputs and then some configs on
>> this regard. The protocol is up. It is pingable and traceable. Yet shows
>> unreachable.
>>
>> bird> show protocol R49624xB
>> Name       Proto      Table      State  Since         Info
>> R49624xB   BGP        ---        up     11:34:07.198  Established
>>
>> bird> show route protocol R49624xB
>> Table T49624_6:
>> 2a0b:880::/32        unreachable [R49624xB 11:34:08.214 from
>> 2001:7f8:4c::ffff:b] (100) [i]
>>
>> bird> sh route table master6 2a0b:880::/32
>> Network not found
>>
>> -bash-4.2# ping6 2001:7f8:4c::ffff:b
>> PING 2001:7f8:4c::ffff:b(2001:7f8:4c::ffff:b) 56 data bytes
>> 64 bytes from 2001:7f8:4c::ffff:b: icmp_seq=1 ttl=64 time=1.04 ms
>> 64 bytes from 2001:7f8:4c::ffff:b: icmp_seq=2 ttl=64 time=0.977 ms
>>
>> #####
>> function is_martian6()
>> prefix set martians;
>> {
>>         martians = [ 3ffe::/16+, 2001:db8::/32+, 2001::/33+, 2002::/17+,
>> ::/8+,  fe00::/9+, ff00::/8+ ];
>>         #if net.ip = :: then return true;
>>         if (net.len < 19) || (net.len > 48) then return true;
>>         if net ~ martians then return true;
>>         return false;
>> }
>> function bgp_in_ibgp()
>> {
>>         if (is_martian6()) then return false;
>>         if gw = 2001:7f8:4c::ffff:a then {
>>                 if net ~ [ 2a0b:880::/32 ] then {
>>                         bgp_path.prepend(myas);
>>                         return true;
>>                 }
>>         }
>>         if gw = 2001:7f8:4c::ffff:b then {
>>                 if net ~ [ 2a0b:880::/32 ] then {
>>                         bgp_path.prepend(myas);
>>                         return true;
>>                 }
>>         }
>>         return false;
>> }
>> protocol pipe P49624_6 {
>>         table master6;
>>         peer table T49624_6 ;
>>         import where bgp_in_ibgp();
>>         export all;
>>
>> }
>> protocol bgp R49624xB {
>>             local rs_IPv6 as myas;
>>             neighbor as myas;
>>             neighbor 2001:7f8:4c::ffff:b;
>>             passive on;
>>             connect retry time 6000;
>>             ipv6 {
>>                     table T49624_6;
>>                     import limit 50 action disable;
>>                     import all;
>>                     import keep filtered on;
>>                     export all;
>>             };
>> }
>> #####
>>
>> Some insight would be very appreciated!
>> Take care of yourselves and stay healthy and home :D
>> cheers!
>> Irène
>>
>> --
>> Irene Lalioti
>> Network Engineer
>> Fondation RESTENA
>> 2, avenue de l'Université
>> L-4365 Esch/Alzette
>>
>> Tel: +352 424409 1
>> Fax: +352 422473
>>
>>
-- 
Irene Lalioti
Network Engineer
Fondation RESTENA
2, avenue de l'Université
L-4365 Esch/Alzette

Tel: +352 424409 1
Fax: +352 422473