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    <p>Hi Pavel,<br>
      <br>
      sadly, BIRD does not currently support setting the BGP aggregator
      attribute. (You can only unset it in the filters using `unset`
      function)<br>
      <br>
      Neither is there a plan to add support for it in the near future.<br>
      <br>
      However we offer commercial feature request contracts, in case
      your organization would be able to provide funds for such
      development.<br>
      You can find more info about it on our website:
      <a class="moz-txt-link-freetext" href="https://bird.nic.cz/commercial-services/#deployments-feature-request">https://bird.nic.cz/commercial-services/#deployments-feature-request</a><br>
      <br>
      Hope this helps,<br>
      David</p>
    <pre class="moz-signature" cols="72">David Petera (he/him) | BIRD Tech Support | CZ.NIC, z.s.p.o.</pre>
    <div class="moz-cite-prefix">On 4/14/26 14:31, Pavel Trefný wrote:<br>
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      cite="mid:075da421-2020-47bf-b29b-2412d21db84e@trefcon.cz">
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      <p class="isSelectedEnd"><span>Hi,</span></p>
      <p class="isSelectedEnd"><span>I have a question regarding BIRD.
          Is it possible to set the BGP aggregator attribute for a
          prefix using filters?</span></p>
      <p class="isSelectedEnd"><span>This would be useful in our anycast
          setup, where it can be difficult to determine the origin of a
          prefix. Using communities is unfortunately not a viable option
          for us — some of our hardware does not support extended
          communities, and upstream networks often filter them.</span></p>
      <p class="isSelectedEnd"><span>To clarify, I am not looking for
          route aggregation itself, but specifically a way to set the
          aggregator attribute.</span></p>
      <p class="isSelectedEnd"><span>Thank you for any insights.</span></p>
      <p><span>Best regards,</span><br>
        <span>Pavel Trefny</span></p>
      <p><span><br>
        </span></p>
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