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<p>Hello Matt,</p>
<p>your preference attribute is manually set higher which takes
precedence over anything specified in BGP.</p>
<p>If you want LLGR to work, keep both sessions at the same preference
and set only bgp_local_pref which is evaluated after LLGR. Yes, these
are different attributes.</p>
<p>Maria</p>
<p>On Mon, Dec 01, 2025 at 12:13:14PM -0500, Matt Corallo wrote:</p>
<blockquote>
<p>It appears bird (2.17.1) doesn’t implement the required LLGR
de-preferencing logic, eg in a simple test environment with LLGR and one
(otherwise-preferred) session down, bird shows it as still selected even
though it has the stale flag (see below). Is there any way to do the
required de-preferencing with filters or would a patch to implement this
be simple?</p>
<p>Thanks.</p>
<p>bird> show route for 69.59.18.0 all Table master4: 69.59.18.0/24
unicast [localsyncb 17:06:58.262 from 10.242.243.12] * (101s)
[AS397444i] Type: BGP univ BGP.origin: IGP BGP.as_path: 397444
BGP.next_hop: …. BGP.local_pref: 101 BGP.community: (65535,6) unicast
[localsync 2025-11-30 from 10.242.242.12] (100) [AS397444i] Type: BGP
univ BGP.origin: IGP BGP.as_path: 397444 BGP.next_hop: ….
BGP.local_pref: 100</p>
</blockquote>
<p>–<br />
Maria Matejka (she/her) | BIRD Team Leader | CZ.NIC, z.s.p.o.</p>
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