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Routes redistributed to BGP peer are sent without BGP community value
Symptoms
  • BGP routes are not sending out correct community attributes in the following scenario:

    1. Example Topology:
      Router_1 [X.X.X.0/Y] --- (OSPF) --- Check Point --- (BGP) --- Router_2
    2. X.X.X.0/Y is learned by Check Point from OSPF and redistributed into BGP using routemap
      routemap "OSPF-to-BGP" sets BGP community N to routes that match OSPF
    3. Router_2 receives X.X.X.0/Y prefix without BGP community value
  • The following commands issued on Check Point Gateway resolve the issue temporarily:

    set routemap "OSPF-to-BGP" id Z action community N as 65200 off
    set routemap "OSPF-to-BGP" id Z action community N as 65200 on
  • Issue is triggered once BGP is restarting on the BGP peer.

Cause

Incorrect logic in iBGP for sending out routes with identical nexthops and path attribute information. This caused routes with different communities to be considered as having identical path attributes and thus sent together in an Update message.

BGP routes are not sending out correct BGP community attributes in the following scenario:

  1. Configure two routes to export to BGP.
  2. Configure a routemap with two IDs.
  3. On the first ID, match the first route.
  4. On the second ID, match the second route and set action to set a BGP community.
  5. Use the routemap to export to BGP.
  6. Both routes are sent in the same BGP update message and without BGP community.

Solution
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