+ Reply to Thread
Results 1 to 4 of 4
  1. Senior Member
    Join Date
    Mar 2010
    Posts
    169
    #1

    Question "received-only" prefix in "show ip bgp" output

    I configured "ip community-list" and "route-map" in router named "r2" in order to prepend AS path, modify origin attribute and decrease local-preference value based on the community value attached to received prefix. This "route-map" works fine, but why do I receive two prefixes and one of those is "received-only"?

    Before the route-map was applied:

    Code:
    r2#sh ip bgp 192.168.1.0
    BGP routing table entry for 192.168.1.0/24, version 13
    Paths: (1 available, best #1, table default)
      Not advertised to any peer
      65000, (received & used)
        10.10.10.1 from 10.10.10.1 (192.168.1.1)
          Origin IGP, metric 0, localpref 100, valid, external, best
          Community: 1111:222
    r2#

    After the route-map was applied:

    Code:
    r2#sh ip bgp 192.168.1.0                  
    BGP routing table entry for 192.168.1.0/24, version 14
    Paths: (2 available, best #1, table default)
      Not advertised to any peer
      65000 65000 65000 65000 65000 65000 65000 65000 65000 65000 65000
        10.10.10.1 from 10.10.10.1 (192.168.1.1)
          Origin incomplete, metric 0, localpref 87, valid, external, best
          Community: 1111:222
      65000, (received-only)
        10.10.10.1 from 10.10.10.1 (192.168.1.1)
          Origin IGP, metric 0, localpref 100, valid, external
          Community: 1111:222
    r2#
    Reply With Quote Quote  

  2. SS -->
  3. srg
    srg is offline
    Senior Member
    Join Date
    Dec 2006
    Location
    Sweden
    Posts
    140

    Certifications
    CCIE SP, CCNP, CCNP SP, CCDA, CCNA DC, CCNA W, HP MASE
    #2
    Are you using soft-inbound-reconfiguration? In that case the recevied-only route are how the prefix was sent to you, before your router applied all its policies.
    Reply With Quote Quote  

  4. Senior Member
    Join Date
    Mar 2010
    Posts
    169
    #3
    Quote Originally Posted by srg View Post
    Are you using soft-inbound-reconfiguration? In that case the recevied-only route are how the prefix was sent to you, before your router applied all its policies.
    Yes, I'm using "soft-reconfiguration inbound". Thank you for explaining this! In addition, if I disable "soft-reconfiguration inbound", I save some memory:

    "soft-reconfiguration inbound" enabled:

    Code:
    3 path entries using 168 bytes of memory

    "soft-reconfiguration inbound" disabled:

    Code:
    2 path entries using 112 bytes of memory
    Reply With Quote Quote  

  5. srg
    srg is offline
    Senior Member
    Join Date
    Dec 2006
    Location
    Sweden
    Posts
    140

    Certifications
    CCIE SP, CCNP, CCNP SP, CCDA, CCNA DC, CCNA W, HP MASE
    #4
    yes soft-reconfiguration inbound keeps a copy of the original prefix pre-filtering stored in memory so it might take up quite a lot of memory depending on the situation.
    Reply With Quote Quote  

+ Reply to Thread

Social Networking & Bookmarks