'prefer older' does not work?

[Arvin Gan]

Hi  Alexander,
   Suggest you confirm with the BGP route selection algorithm bgp_rte_better,  the option "prefer older"  will  work  only when all pervious selection options are the same. 

Best Regards,
Arvin Gan

-----Original Message-----
From: Bird-users <bird-users-bounces at network.cz> On Behalf Of Alexander Shikov
Sent: Monday, May 13, 2019 5:49 PM
To: bird-users at network.cz
Subject: 'prefer older' does not work?

Hello!

All of our BGP peers have 'prefer older' option enabled. 
But I noticed that best route is not the oldest one:

bird> show route for 91.226.190.1 all
91.226.190.0/24    via 193.25.181.44 on bge0 [ITSTARCOM 2019-05-10 11:05:56] * (100) [AS50981i]
        Type: BGP unicast univ
        BGP.origin: IGP
        BGP.as_path: 48422 50981
        BGP.next_hop: 193.25.181.44
        BGP.local_pref: 100
        BGP.community: (65005,10804) (31210,31210)
        BGP.ext_community: (rt, 31210, 31210)
                   via 193.25.180.141 on bge0 [SATELLITE 2019-05-09 15:16:08] (100) [AS50981i]
        Type: BGP unicast univ
        BGP.origin: IGP
        BGP.as_path: 44416 50981
        BGP.next_hop: 193.25.180.141
        BGP.local_pref: 100
        BGP.community: (44416,2) (65005,10804) (31210,31210)
        BGP.ext_community: (rt, 31210, 31210)

What am I missing?
Thanks!

-- 
Alexander Shikov
Technical Staff, Digital Telecom IX
Tel.: +380 44 201 14 07
Mob.: +380 50 410 30 57
http://dtel-ix.net/